As an American myself, perhaps I can help explain this. We are more divided than ever before, with one side literally spouting neo-nazi propaganda (and both sides aiding genocide), and many of us expect if not quite a full-on civil war, then at least some kind of "Constitutional event" akin to the January 5 riot at the capitol to take place in the next few months.

Though whether that ever comes or not, our democracy has already fallen. For one thing, the recent(-ish) SCOTUS ruling a few months ago allows the President to literally assassinate their political rivals, fully legally, with very little oversight (I'm not aware of the particulars tho), thereby giving them (whether they ever choose to use it or not) the powers of a totalitarian dictator. And this barely scratches the surface of what all is going on with our judicial branch...

And for another, every single year Congress refuses to pass a financial budget, instead kicking it forward for months at a time as they bicker about the details, though more importantly, one side considers this obstructionism a "victory" - and this same side is the one actually putting out the call for a full-on Civil War, no joke. And this as well barely begins to scratch the surface of all the brokenness of our legislative branch...

And too the over-turning of Roe v. Wade, like the handling of the pandemic, has scared people. The same person smiling sweetly across the table as you eat Thanksgiving dinner (American holiday celebrating the "discovery", prior to the slaughter of the "Indians", by the "Saint" Christopher Columbus) is the very self-same one who if you die in the next couple of years, they were someone who helped make it happen. As in: if you don't want an abortion, then don't get one, but preventing others from getting not only "abortions", but from removing things like cancerous masses in the uterus or even already-dead, necrotic and rotting fetus left-over material, b/c of someone's fucked-up definition of what an "abortion" is. Someone who btw does not have an M.D., a Ph.D., a J.D., or any other kind of professional degree that would lend towards understanding what a "fetus" is or is not, and instead rants and raves spouting nonsense about "Jewish space lasers" and the like.

This shit is literally life and death for us. School shootings are real - and not merely limited to schools, but also shopping centers, theaters, and the like. Heck, the former president has already had two very inept assassination attempts already. We are a nation in turmoil, having already received what looks to be a fatal wound, and now just waiting to die and/or see whatever will come next. Our votes barely matter, as regardless of who we put in, the wealthy elite control them - e.g. 90% of people want some form of responsible gun control laws, yet time after time voters put people into place who will enact them yet it never happens, those people going in get bribed or blocked and then never manage to get it done, thus leaving our children to be sacrificed to the alter of greed. And ignorance. And especially obstinacy.

But setting aside all of the above, conservatives tend to be not very "fun" to talk to. I don't even mean true "conservatives" but rather what ended up replacing most of them, first with the Alt-Right that replaced socioeconomic conservatism (e.g. progressive conservativism from the Bush era gave way to the likes of Mitt Romney and Ted Cruz) and now with the Trump-focused Maga (+ the likes of Marjorie Taylor Green, and outside of politics people like Alex Jones and Joe Rogan). If you watch Innuendo Studios' The Alt-Right Playbook you can see a large litany of "tactics" used to control and twist every conversation, which often do things such as ignore most of what the other person said while hyper-focusing on a singular aspect that they then twist and distort to unrecognizable proportions before preemptively claiming "victory". Seriously, I've genuinely had better conversations with 5-year-old children.

That doesn't mean that people "like" the Democrat, left-leaning party, with its neoliberal attitudes of only pretending to care about the common man while instead enriching the wealthy, it just means that many people - especially educated ones such as we see more often on the Fediverse - "dislike" the Republican, right-leaning party, with its neoconservative attitudes of only pretending to care about the common man while instead enriching the wealthy, oh and also killing people (e.g. blocking abortions) on top of that.

I don't think most people would mind debating a real conservative though? One who was respectful and perhaps even kind? Especially if they stuck to factual argumentation rather than made-up "alternative facts" bullshit. It's just that those are so exceedingly rare as to barely exist these days. But look around - I have seen entire communities devoted to such things, and as you pointed out there are entire instances that are dedicated to them as well. Also there's Truth Social, X, and most mainstream news sources that at least offer that POV a platform - e.g. the second presidential debate with Kamala Harris lacking real-time fact checking, thereby letting Trump say just whatever he wants at any given moment. Truthfully, I do not feel that "conservative" POVs are in any way in danger of dying off. Though that does not mean that it is welcomed into every single spot across the entire internet either.

Conversations must be held in good faith. Conservatives often refuse to do so. Hence, the defederation has little to do with them being "conservative", and much to do with them being "toxic" (although those two things are not entirely unrelated...).