You all waited for this for a long time, and now you can delete members of your forum, on your own!
As admin of the forum, if you go to the members page, click on the 3 dots, below the block member option, you also will see now the delete member option:
Deleting the member will also delete all the member posts, comments & likes.
So use this new power with responsibility :)
In order to have this feature on your Wix Forum, you need to:
Go to the editor
Open the forum settings
Update to the new forum version
Publish your site