I'm rather disconnected from the world but whenever I check the news it's about people who are supposedly trying to change the world. — TheMadFool
Perhaps, it shouldn't surprise you that this is what you find on the news, but you maybe mixing different kinds of self-identified "world changers" and generalizing the disingenuity and poor arguments of some to all.
I would argue your impression should not surprise you, because anyone trying to make any change at all will claim that A. the world needs changing and B. that their proposed change is good.
Many in this group, however, may not actually believe in these statements, rather they may just believe it's the statements to make; i.e. marketing. For instance, a corrupt politician (who is already corrupt and not fooling themselves about it) won't make the statement "I'm corrupt, vote for me" but rather they will market themselves as bringing positive change. Likewise, corporate lobbiest, executives, funded academic, conflict-of-interest pundits, funded think-tankers, or otherwise corporate representatives may have no illusions that they are presenting an argument in the news that is good for the corporation that is paying them to make those said arguments, and it's not good for the world in general and they are only making these arguments because they are being paid. There are also useful-idiots in the same categories that have no critical thinking skills; they may actually believe the proposed A+B arguments, and are funded precisely because they champion that view. Likewise, for non-profit groups such as religions, NOG's, social movements of various kinds. And beside these, there's the "silicon valley startup" culture, darlings of main stream media, that, if you are dissatisfied, are offered up and fawned over as the "radicals" that are going to shake up and disrupt business as usual; and again, whether they believe it or not, it's better marketing to say your new service or product is making the world a better place.
Now, this is not to paint all politicians, corporations, non-profits, religious organizations, and entrepreneurs with the same brush, my entire point here is that we can not generalize from a particular self labelled or media labelled group, and we can expect, and certainly can't exclude, that the self-aware disingenuous "world changers" as well as useful idiots they employ appearing in the news; it likely follows that someone with critical thinking skills will not be very convinced by arguments from this group. And, more importantly, if the mainstream media was a terrain that not only allowed the disingenuous and useful idiots but actually favoured them (perhaps because corporate news is not a neutral organization itself or it they are simply doing there job and "giving people what they want"), then we might expect to find exactly the following observation:
I guess by ''change'' people want to give the impression that the efforts of these people, who hog the airtime on networks, are positive; an improvement so to speak. — TheMadFool
I don't want to put corporate news on trial, here, I simply wish to invite you to consider if your observation is surprising or not.
What I wish to focus on is the underlying question of your post, that is if "world changing" itself is a fools errand or not.
You seem to be aware that in the past world changing was probably needed as well as aware that, being largely disconnected from the world that the people who surround you represent a statistical selection bias. You see little need for world changing around you and your argument that this sentiment might be generalized seems to rest on remaining unconvinced by the main stream media. Since you already have 2 premises needed to challenge your view, I'll leave you to inspect the third.
I'd also like to mention that between the disingenuous and useful idiots groups above and well the genuine, well reflected and, if not correct then compelling interlocutors, there's of course a large spectrum in between, of genuine but confused, inarticulate or even counter productive people that are perhaps right in their feeling that the world needs changing but are unable to formulate their reasons for this, much less what would be efficient action with respect to it. Again, if these people are often on the media, perhaps because they're a lot of them or perhaps because they are useful targets or perhaps the media really is neutral and just giving a platform to everyone, then it likely follows, even they are right about some things, that they are unconvincing.
The point I'd like to focus on, is the the positive argument that some world-changers are correct, of which I'd self-label myself as apart and so feel responsible to defend this world view on the forum; of course, as a tiny part of my world changing mission.
There are many arguments of why actively changing the world is a worthwhile endeavor, but I'll focus on two.
The first, is that, as you mention we pretty much all believe slavery was bad and that people were in the right to actively endeavor to end slavery. If we consider this believe as correct and we look closer at it, we find that the question of slaver was not one of number, that "most people were slaves" or even "most slaves are treated brutally" but of type, that slavery itself is morally repugnant. Slavery is still very much a thing and if we believe the abolitionists had the the right cause, then it's extremely likely that they would not have consider a resolution of slavery simply calling slavery a different name, but that exactly the same or sufficiently similar conditions to slavery fall within the same scope of the slaver-is-bad argument. Since it is not a question of number but of type, then it follows we should continue to change the world to abolish slavery until the task is done. Likewise, the same argument applies if we believe people who fought for democracy were in the right until the entire world is democratic (the counter argument that some people don't "want to be democratic", well if it's the majority who feel that way then the only way to check is through democracy).
The second argument is to simply look at the present and talk numbers. Are (entirely preventable) wars and famines affecting millions morally justified to do nothing about? If someone was starving right in front of me, would I act? What changes morally if the person is far away? What can practically be accomplished, if anything, is a much harder challenge but does something being inconvenient or difficult sufficient grounds to dissolve moral responsibility? If we turn our attention to the West, though I would agree we need not worry about the middle class, there are a large number of people in poorer classes: should we care? essentially depends on whether the status quo is justifiable justifiable.
The third argument is to consider whether the global economic system is sustainable. If it's not sustainable, regardless of whether one believes it would require large or small change, then the definition of not-sustainable is that it will come to an end on the one hand and on the other that the process of being unsustainable is the destruction of conditions, in other words nature. From here, one can argue that even if one cares not about the slaves, the oppressed or the down-trodden because there is not enough of them or it is entirely self-inflicted suffering, and one only cares about middle-class Western life style as a "good thing", then if the system supporting this life style is not sustainable then presumably there is some basis to act to make it sustainable; otherwise it's difficult to say it's a good thing as you seem to suggest in your post. The other direction this can take is that preserving the conditions for human civilization, whether the value is placed on civilization or nature, is a moral responsibility; that every avoidable extinction is a tragedy and we should strive to avoid more of them. The question of whether our economic system is sustainable -- or even if it is not whether it will simply self correct without anyone doing a particular effort above what would otherwise fancy them to do -- is of course an empirical question with a significant amount of resources available.
Before discussing the empirical (not only is perhaps the system sustainable, perhaps there are no slaves or no sufferers that choose not to suffer), and in particular for a philosophy forum it is I believe more fitting, I am here only defending that they conclusions follow from the premises: that if there are slaves, then we should "change the world" until there are no slaves; that if there are preventable wars and famines and preventable undignified working conditions, we should act to prevent these things; that if our system sustenance and shelter is not sustainable we should act until it is sustainable. Would you agree or disagree that these arguments are sound?
If there is agreement, then both the empirical questions as well as what actions, if any, are effective and which, if there are several, are the most effective, would be the next pertinent issues.