Follower count has never been accurate in Nostr.
Discussion
It is my only way to determine bot, or not, as they rarely have many followers.
npub.world is the best bot/not bot checker. Second to that, and built into an actual client, is #Coracle by nostr:npub1jlrs53pkdfjnts29kveljul2sm0actt6n8dxrrzqcersttvcuv3qdjynqn.
Who you follow *is* generally accurate because it is contained in 1 list which is easy for a client to retrieve. Your followers has to be pulled from every other user 1 at a time, from multiple relays, which is way less accurate.