[csee]

> The problem is that these crimes often vary so much that it's hard to find a common thread besides vague ideological motivations.

I agree that it's hard, but some scholars have argued that there is a common thread. Why wouldn't we want to put that scholarship on Wikipedia?

> Are there other Wikipedia pages in the style of "mass killing in .*ist regimes"? I couldn't find one.

There's this, but it's not well developed.

https://en.wikipedia.org/wiki/Colonialism_and_genocide