Mastodon can be heavy on censorship by banning IP addresses rather than individual accounts. Not banning an account, but IP. So when one instance bans an IP, that means that IP is blocked from all users on that instance.
Twitter has never banned IP addresses, only accounts. Twitter does not keep a list of naughty words that result in immediate ban after posting, and suspended users can still reaxh Twitter to discuss the issue.
It seems that federated platforms are more ban happy than the corporate platforms. If Lemmy and Mastodon really want to challenge the bigger companies, protect offensive posts, protect mockery and insults, people challenging or correct someone's statement, and distinguish them from actual attacks and degrading words.