I would from personal experience disagree on the "well" part.
I'm suddenly following accounts I recently unfollowed again. Previously blocked accounts show up. The search doesn't find stuff it used to find anymore - posts that are definitely not deleted because I can usually find them via other references.
I have noticed that the explore page, and my timeline are way staler than they used to be. Tweets I have seen or even interacted with keep popping to the top all day, and trends on the explore page can be there for days at a time. It can take hours for major world events don't show up on the explore page for me sometimes.
I would from personal experience disagree on the "well" part.
I'm suddenly following accounts I recently unfollowed again. Previously blocked accounts show up. The search doesn't find stuff it used to find anymore - posts that are definitely not deleted because I can usually find them via other references.