This issue still persists in 2.9.2. If I first log in as a viewer, open a table (I cannot edit), and close the table, the table becomes locked by that user. If I then connect as another viewer, open the table and close the table, now there are two locks on the table (shared). Then if I connect as an editor, even though I have the permissions, I cannot edit the table because of the locks. If I disconnect the first two users, the locks will be removed, but the table does not really unlock. In other words, the editor still cannot edit the table even logged on as a user with edit privileges. Only restarting ArcGIS allows for the editor to edit the table as the first person to connect and open the table.
Similarly, it seems the opposite problem persist. As stated above, if the first users are viewers then the subsequent users are only viewers until ArcGIS restart. If the first users are editors, and the subsequent users are viewers, then these viewers have the ability to edit even though they truly don't have the privilege, but since the table is still locked by a user who can edit, then folks with subsequent connections also have the editing rights. Similarly, if the initial editor is manually disconnected thereby removing the lock, the file will not behave correctly (disallow editing) until after ArcGIS is restarted. It would seem this could be a significant vulnerability.