It's true. It's why I feel that Mastodon will never replace Twitter. It's too much of a left wing circlejerk / bubble, and they're actively hostile to even moderate viewpoints. much less actually conservative ones.
I'm probably in the minority in this, but I believe that even people I don't agree with should have a platform and be tolerated as long as they're reasonable and willing to compromise and show respect, as long as they're not racist nazi nutjobs.
The world isn't exclusively made up of one set of ideas, and you shouldn't shut out 75% of all viewpoints just because they don't agree with yours, imo.