We get reports, and that's great. But sometimes we also get reports for people who have already been banned, it's just that their comments weren't removed.

You can differentiate someone who was banned by the lack of a profile picture next to their name. All users since a few lemmy versions have a default pfp of the Lemmy mascot. If there's no pfp there, it means they were banned on the instance you're looking at the comment from.