FWIW they have instructions for downloading the whole thing, which mention that it is also downloadable from BitTorrent. So I think it is functionally impossible to delete Wikipedia.
I’d be more worried about propaganda being inserted.
I'm not worried about the data, and even losing the servers would be a hiccup. But whatever site is at www.wikipedia.org is, in the minds of the general public, Wikipedia.
I imagine most traffic to Wikipedia is through search, so I imagine such a fate is in the hands of search engines. If a community-driven alternative appeared, we'd have to rely on Google indexing this alternative and ranking it higher than the usurped domain.
It's been called "wokepedia" (not to be confused with Wookieepedia, the star wars wiki) by Musk and others, telling people not to donate.
And also people have been denouncing Google's search results as biased, as being "woke".
I'm still not sure what any specific user of the word "woke" means, beyond the Ami/UK right using it as an insult, but I can't tell if it's generic or specific, critiquing something or just telling supporters when to boo and jeer. Does the Ami/UK left still use it to mean "being aware of systemic prejudice", or have they also shifted? I didn't notice at the time when "meme" stopped meaning shared online quiz.