@MayLouise @erindickins as I said up thread, mstdn.social is not mastodon.social. These are different, but named similarly.
As for what happened? This was the latest incident, but not the first. This time, a post was removed for racism. The post in question was about not reading books by white guys.
It may have been a mistake, or the decision may be reverse, or the whole thing may have been faked (unlikely, but possible.) It's hard to say! But it's not the first time a thing like this has happened. That instance has too many people and not enough moderators.
@erindickins mstdn.social is not the same as mastodon.social.
That bit is unreasonably confusing, and I wish it was easier.
mstdn.social and mastodon.social are unaffiliated as far as I'm aware.
You're fine, although you might be happier on another instance at some point in the future, or maybe you won't.
Thankfully, migrating between instances is pretty easy, should you decide to do so in the future.