Administered by:
If there are people spamming or misusing a hashtag, mute or block as much as possible. It is fine to mute or block, it isn't seen as a personal insult on here.
On most tags there shouldn't be problems anyway (for example #Mosstodon, #BreadPosting, #Lichensubscribe etc are wonderful), but obviously tags related to controversial things will attract more problematic posts.