There's this hubris in the western left to think materialism is just a way of thinking that lets you understand everything just by virtue of being rational.

"Look, I'm a materialist, so I say, colonial powers aren't especially evil, they're just big countries and every big country just want to exploit the smaller countries."

I wouldn't say that's inherently stupid, but it's extremely ignorant of all the work done around the question of colonialism. But it's fine for the white lefty overconfident enlightened ones who can figure out everything by themselves.