there r lots people who post reddit then delete account. extremely annoying, and coward. not talking about sensitive topic even. e.g. on #emacs.
young people, use your real name on social media. and, stand for what you say. don't shitpost. that's how you respect yourself and earn respect.
there r certainly situations anonymity apply, e.g. the work wikileaks is doing. but mostly (i'd say 99.99% posts), the nameless account behavior on the internet is just cowardice and irresponsibility.