This isn't about the money.
Hamilton is angling for an influential life outside of F1, and greater control of his image, while he is on top of the world. It's smart, albeit a game of brinkmanship.
If his relationship with Toto and Co. were entirely limited to driving the car, I think he'd be overplaying his hand. As that is not the case, he has the high ground.
Mercedes would want Hamilton in the car for 2022, but I don't think they have him penciled in until 2024.
I think some form of compromise contract will be reached, with a 2 or 3-year deal at 40-50M per year.
That said, stranger things have happened.