I'm surprised when I see a comment ascribing this to Elon deleting things upvoted higher than the comments that explain this is a normal part of how Community Notes work for so-so notes.
I'm a member of Community Notes and while it's common for an unpublished note to be downranked by members, I have never before seen an example of a published note (visible to all Twitter/X users) later be withdrawn from visibility. In fact, I don't think there's even a process for Community Notes members to make that happen.
I'm also a member of Community Notes and I've seen it several times, as well as explanations from Twitter staff that this is how it works (this was pre-Elon).