Whats the point of writing prn, f@ck, sht or anything like that instead of the actual words? You can still read them, its not like they are gone if you replace a letter or two.
On Lemmy, there's no good reason. But they may be carrying over habits from other sites where there is harsh censorship of non-advertiser-friendly language
I have been watching Rick and Morty lately and every now and then I have to change the site to find a version of the episode I'm watching where swear words aren't censored. Like, it's a show made for adults full of violent and sexual themes, so I think that most viewers have heard the word "fuck" before. I hate it so much when people censor "bad words", even though nothing prevents them from saying them.
One possible reason is that some words on controversial subjects can attract mobs of posters with an agenda. They search for keywords to find threads to flood with their arguments.
So posters would get in the habit of saying something like "I love p1n3apple on p*zza" to avoid the wrath of pizza purists (made-up example, but substitute with anything more controversial).
Generally I don't care about words like bitch, fuck, shit, but there are certain servers and communities where cusses or other words are used harmfully towards groups that the community or server is inteded to be a supportive place for, and when they come up in discussion, even just as examples as what was said to them are rightfully censored or have a trigger warning placed in front.
Community mods and server operators can get overboard with this but they get that privilege because they do the work to moderate it anyway.
I have a habit born out of having young kids around of cartoonizing more expressive language that leaks over into online conversations. There might be a bit of that going on along side the more censorship style responses put out elsewhere.