Gregory's Server
Moderation depends entirely on the instance you join. Every instance has its own admins and staff (or maybe no staff). Every instance has its own rules for what is and is not allowed.
This is an especially important consideration for minorities.
Anti-LGBT and anti-BIPOC posts are perfectly acceptable on some instances.
I agree that Mastodon is still better than the alternatives, but it is not a perfectly safe space.
The nature of federation means there are islands of safety and oceans of doubt.
Just be careful.