The urban dictionary will be maintained in perpetuity. It is too funny not too.
Aside from data degradation and selective retention it will be interesting in a few centuries that is for sure how language evolves.
Things like Standard American English and the like may be maintained to pretty rigorous standards. Also a lot of native language preservation happening around the world right now with digital recordings that will get archived properly.
I was joking the other day about how algorithms may do more to change language than anything else. Someone decides a word is objectionable and it gets added to a social media ban list. People adopt a new term and so on. Then we have whole cycles of word use decrease/increase.
Like how the internet uses the term unalive instead of death/suicide. Or how people came up with joke names to talk about Covid without getting censored.