The reasons civilized, humane people object to public hangings, drawing and quartering, skinning alive, burning at the strake, chopping off hands/tongues/penises and anything liable to a clever, are four-fold:
First, performing torture unto death is an inherently dehumanizing, degrading experience for the person elected to perform the task.
Second, legislating torture unto death dehumanizes and degrades both the legislators and their electors
Third, viewing a torture unto death (these sorts of things have always been popular where allowed), is dehumanizing and degrading to the observer,
fourth, being tortured unto death is dehumanizing and degrading to the subject.
Everyone involved in torture unto death, either directly or as indirectly as merely approving of this kind of punishment is contaminated by the retrograde act of ancient tribal justice.
All this applies to torture short of death, as well.
Look, we're making some progress. Many in the world disapprove of female clitorectomy, female disinfibulation (scaring the vagina shut prior to marriage), and male circumcision. Foot binding in china was ended... about a century ago. There are laws in many countries (particularly in the West) against torturing people to extract information. There are strong objections to putting prisoners in solitary confinement for periods longer than... 3 days, is it? (Some prisoners have been kept in solitary for months or years.) Most countries in the west have patient protection through informed consent.
#MeToo gets people fired for unsubstantiated claims of sexual harassment. Transexuals, Transgendered people, and homosexuals have legal protection. Et cetera.
If being hanged, electrocuted, drugged, gassed, shot, or strangled doesn't prevent people from committing capital crimes, I don't think making this even more grotesque will do the trick.
We have to accept that a certain number of slight, moderate, and very bad criminal acts will occur in society. they will range from shoplifting to serial murder and serial rape. The best we can do is try to prevent crime (we really don't try very hard in that area), rehabilitate criminals (we flat-out fail in most cases) and separate dangerous people from society (right now we separate way, way too many ordinary criminals from society -- at huge expense with no benefit to anyone except the prison business of states and private industry).