Most of mine are gone too. I think the server has limited space.

I used to have almost 700 posts and nearly 15k comments but now I have less than 400 posts and 13k comments. So yeah, the limited server space is probably the reason.

Since this is the internet and logical explanations such as those aren’t allowed we must say it’s the Mandela Effect

I have a post that says it's my 600th post