I don't know anyone that self defines as "absolutist", but many that simply are that way.
My elementary school was a religious one. There was something that deeply annoyed me about how they reasoned. I couldn't put my finger on it then, but I got a knee-jerk reaction as soon as I heard it. It was just that: love is better than hate, virtue is better than sin, etc. so you must comply with what God/they/your parents said because they loved you vs. your bad instincts, inspired by the devil that is Bad.
By the time I started high scholl in a public school, the dictator had died and we transitioned to democracy. Tolerance was the magic word. We can now speak our minds, accept others' opinions, discuss frankly any idea.
But then the left was the forbidden set of ideas making itself a space. Forty years later they're hegemonic and "zero tolerance" (I hate that expression) and beware of what you say are back.
They're exactly the same as their parents (that they consider troglodites) just with a different set of dogmas. Ideas change easily with the fads, but mindsets not so fast.
The trick is to present an idea that's absolutely good on paper like: "don't you think that everybody should have what they need to live?" But ignoring all the practical details of implementation: if it's at all possible, if the proposed measures are useful to reach that goal, etc.
No one of them would call themselves "absolutists", that sounds like ancient regime, or fascists, nazis. But they reason in absolutes and there's no way to touch them with words. They won't negotiate because they just vote for politicians that promise to magically implement that wishful thinking. The politicians will negotiate to reach power, though, they know better.