I am not criticising as a motivator, I agree that people make an effort to understand each other only because empathy caused them to care in the first place. I consider this to be the strongest counterargument to my position, it was something I knew already but my interpretation is that empathy as a motivator is not helping you to understand, it's just making you want to understand but I will respect disagreement on this issue.
I think you had many opportunities to bring up less contentious examples than things like slavery and police targetting of black youth, which are fairly preposterous examples that are easy to dismantle.
Take something like empathising with someone losing their car keys, it's annoying to you so it's a fair assumption that they find it annoying too. Everyone decided to bring up trying to empathise with groups or empathise on complex issues and represented the worst in utilising empathy as a tool for understanding people.
I am sure in the cases where you listen to what people are saying, you read their body language and try to confirm/deny assumptions you're making - that you reach a greater understanding. The question remains as to whether empathy did anything to help. If you had gone and talked to someone, asked them what's wrong, listened to them and asked them how they felt about it - you've already got all the information you wanted to get by using empathy. So what was the point of imagining it?
I think empathy for better or worse, suffers from implicit biases which are extensive and you may take what they say and try to imagine what it's like but it's more likely you're wrong than right and by quite a margin. You may get pieces of the truth which you could then further seek to confirm/deny but once again, why didn't you just ask more questions instead of imagining things?
As for groups, go do some research, listen to people and try to understand the facts. I don't know what information you're seeking to attain through empathy that you can't get a far more accurate picture by just doing a little research or investigation (by asking questions for example). I've asked you but you haven't given answers.
If you want to agree to disagree then it's probably for the best, we've been going in circles for a while now.
EDIT: I always want to mention that you can make logical conclusions without empathy.
Another Kitchen Nightmares example which I think is pretty instructive on this you can watch if you want but I'll just explain:
https://www.youtube.com/watch?v=lUvl9D_IMW8
Sushi Ko is a failing Japanese restaurant with an old chef as an owner named Akira who no longer cooks. When Gordon Ramsay eats there, he thinks the food is disgusting but he already knows that Akira should be aware that the food is awful. Usually people either defend the food (denial), act defeated (given up) or accept they're wrong and don't know what they're doing.
When Akira a chef who should know better didn't argue back, it seemed obvious for Gordon to assume he's given up and when he talked to the family and they agreed, this seemed all but confirmed.
We don't need to empathise with Akira, his actions speak for themselves and with a little insight, we can make strong causal arguments that didn't require us to just believe everything Akira says.