My favorite example of this is people self-censoring “shooter” as “sh**ter”, which I can’t help myself from always parsing as “shitter”.
“The shitter in Virginia has been apprehended”, etc.
What a ridiculous take. Many platforms and games actually prevent you from posting certain words, or flag or otherwise penalize posts if you include them. In some cases, this is completely explicit, i.e. you'll get a message saying "cant' post that."
Instead of playing a guessing game of which platform censors what, it's common just to avoid such words by censoring, euphemisms, or synonyms.
TL;DR: self-censorship is so prevalent because it saves online platforms money.
People: complain to politicians when egregious content starts trending
Politicians: bug Platform to do something about the egregious content
Platform: quickest fix for egregious content is dumb pattern matching
Content Producers: avoid becoming a false positive by using dumb substitutions to dodge the dumb pattern matching
The most direct fix would be the platform getting smarter about censorship, but this would not be without its own tradeoffs.