I've had mixed success with this. It works when you have a nice person going through a tough time in their life who doesn't realise they are reacting badly to everything. I don't think that applies here because this person seems to believe their rudeness is justifiable.

A habit of being an asshole is not cost effective to fix. And giving validation to their belief that they should have "important jobs" just gives them real power to bully you more.

Instead of rewarding bad behaviour, they need an unambiguous dressing down from someone they respect, and a PIP. But IME it's a waste of time, rip the bandaid off and get someone with better default settings.

> And giving validation to their belief that they should have "important jobs" just gives them real power to bully you more.

I think this guy's manager said he won't fire or move him. So then if to avoid sabotage you must respect him and give him important tasks then that's what you do. Even if you think it harms the company. Then you show how it harm the company and you win.