I'm only noticing this on tchncs.
The couple first posts on the "Hot" "Subscribed/All" sorts on tchncs seem to be "normal" hot posts, but after around 15 of those there are only weeks/months/years old posts.
I searched for issues on the repo and I found this which may have been applicable: https://github.com/LemmyNet/lemmy/issues/3125
However, it was fixed for 0.18, which tchncs is running, and theoretically update_hot_ranks should be a startup job, which I assume happened when updating.
Can something be done about this? Maybe cross-post this to [email protected] (though this should probably be done by our friendly admin)?