Some fediverse apps support it. Voyager is one of them.

In Voyager, go to Settings -> User Tags
and you can enable it there. Then go the the user profile of the person you want to label, select the 3 dots at the top right side of the screen, then “Edit Tag”

Cheers.

Considering the label I have for you on Lemmy, I’m pretty sure you were more likely banned for comments inciting others to murder anyone who’s rich.

Naw, they totally called it. Check out the Terminator 2 - 3D show that they used to have at Universal Studios (1996):

Edit (this video link is better): https://www.youtube.com/watch?v=KfvD6UlKSWw&t=1005s

https://www.youtube.com/watch?v=AIoeMLwEIDM&t=1204s