Iv seen posts with people substituting rape with r@pe. Other than bypassing filters I can’t see a reason to censor just 1 letter that doesn’t actually censor the word? I see if you fully censor the word, but even still context completely ruins the censorship.
A lot of this self censoring is algorithm voodoo. Nobody knows what makes these platforms mark your videos as age restricted, so people do silly stuff like say, “unalive”. I’ve seen many videos where people use the word kill that aren’t age restricted.