It feels like the trend has been in the other direction. In most services I've interacted with recently, the service often doesn't even tell you that the content has been removed, let alone why. One example is Discord - if a mod removes a comment you made, it just disappears. You might try to repost it, thinking it failed to send. Similarly if you are removed from a server, it simply disappears from your list. This kind of thing is very frustrating/confusing - not that I expect a mod to necessarily provide explanation (though, that's nice) but at least the service saying "hey, that got removed" prevents me from trying to repost it.
The usual explanation involves spammers/scammers. Something like, if they know they got removed for violating some rule or the other, they can use that information to work around it in their next attempt. But for actual human users it can be very frustrating.