Also, I think it's important to separate "left of center" and "leftist". Liberals and leftists are very different. "Progressive left-liberals" are fans of democracy and freedom and don't like bigotry and authoritarianism and Trump. "Leftists" are often fans of Lenin and Stalin and Pol Pot and killing groups of people who aren't ideologically aligned and instating one-party dictatorships and violently suppressing dissent. In leftist parlance, "leftist" = "Marxist" while "liberal" = "capitalist belonging to the moderate wing of fascism". In the US, politics is best described as not two but four factions: leftists, liberals, rightists, and neo-Nazis. Often neo-Nazis will form coalitions with the rightists to help achieve major goals; historically leftists would form coalitions with the liberals, but this seems to be occurring less and less.

Although leftists will insist the notion is absurd and anti-intellectual, horseshoe theory contains a lot of truth in it.

It's like 50x less of an issue but I deal with so many left-wing conspiracies on a daily basis. I think the right is much worse than the left (on this topic and in general) but quite a lot of the left, or at least the populist left/populist far-left is, to me, its own particular sort of exhaustingly insufferability. I am proudly a left-liberal and not a centrist and never won't be, but I am still at a point where I can no longer tolerate a big sub-faction of the left. (Though I can't tolerate basically any of the right, minus a bit of the anti-Trump center-right.) I am going to lose my mind when I see vast numbers of leftists demand people not vote for the Democratic party presidential candidate in 2028.