For anyone wanting to remove these this is the way.
/player [name] privilege revoke gamemode
/player [name] privilege revoke give
/player [name] privilege revoke tp
/player [name] privilege revoke time
/player [name] privilege revoke grantrevoke <-- this one last. it takes away your privilege to grant or revoke privilege's.
This will be in effect on all of your single player world files, there is a way to undo it. but I'm not going to tell you how.
I really hope they just remove admin privileges from single player worlds, there's no need to have them.
I used to play a lot of RLcraft, but while watching a YouTube tutorial on making some gear, it suddenly showed how to switch the game into creative mode. It completely ruined the experience for me.