That's unduly pessimistic IMHO.
A passenger who is violent/disruptive/abusive will still be able to be offloaded under the terms and conditions that he/she accepted when buying their ticket. Yes, you will need to be sure to follow the procedure to the letter, but don't you already do that?
And if a flight is cancelled because of weather or the aircraft goes tech, your bolshie passenger is hardly going to cling to their seat while everybody else disembarks - what would be the point?