Clicking delete on one server does not magically delete content on other servers, federation needs to happen first and there’s usually a queue for that. If the delete command hasn’t reached remote servers yet, those servers will receive upvotes, downvotes, reactions, you name it. Your local server will likely refuse most of those, but other servers who have a copy of your comment will have a differing local state until the delete request makes it over. If your server, or the remote server, is slow for a while, federation can take minutes to hours to complete.

Not only that, I can restore your deleted comment/post on my server and start commenting on it. My comments will only show up locally on my server, but funky deletion behaviour is just one of the ways Lemmy and centralised platforms differ.

On most servers, the post table is a lot smaller than the comment table, so even on your local server the delete button may take a moment to work, though I wouldn’t expect that to take too much time.

I’m not sure why your deleted stuff is still collecting votes, I think the server should be refusing those. Maybe there’s a bug somewhere?