Assuming GTA 6 isn't a sham filled with expensive technology with poor execution, the content it supposedly would have wouldn't make $100 dollars outrages.
It isn't Call Of Duty yearly release so paying 100 dollars for a game with a billion-dollar budget (supposedly) game with competent developers isn't the worst thing in the world.
People who complain about 100 dollars is just whinny, like don't buy the game then, wait for the price to come down, and if other developers follow suit, then don't buy their games and they'll learn.