The instance itself did not do a “big land grab,” users on the instances made the communities. And, as you should know, the fact that there’s a community on one instance doesn’t mean that the same topic can’t be on another, there are several of those kinds of duplicates.
I signed up for .world because I liked the policies, it didn’t seem to be heavily communist or hosted in an authoritarian country, and it seemed to be robust. Nobody told me I should make my account there; I saw zero advertising. I’m not sure what you think the admins did to make other people settle there.
And the fact that some people are donating to it in no way means they’re making anything like profit. The admins didn’t make a plea for me to donate anywhere that I saw, other than having the link in the sidebar, like many/most instances.
You seem to be taking frustrations out on people who don’t deserve it. If the stability problems become an issue, people will just make accounts elsewhere.