Wikipedia itself is still one of the best resources on the internet, and they actually make it pretty easy to back up their data, which is why there are so many clones out there.

If Wikimedia foundation died, somebody else would take over, and hopefully the quality wouldn’t decline too much.

Reputability and reliability will absolutely take a deep dive.

The greatest asset of Wikipedia is not the trove of data (I have the copy on my computer), but efficient moderation, neutrality, and trust.

None of the clones are nearly as trusted, as they’re edited at a whim of whoever owns them, or simply poorly moderated.