I mean if you’re not interested in fully entertaining the hypothetical, realistically, Prigozhin was very unlikely to achieve much either. Not only would there be a threat to his legitimacy and life from Putin himself, but also even if he somehow got to Putin, it would drastically destabilize the government and open the door to a revolution or another coup. In authoritarian and fascist countries like Russia, everything rests on the figure of the leader.

Moreover, there’s a difference between Prigozhin criticizing from the backseat and actually being the president. The West alone would be trying hard to offer him enough to get him to stop the war, and he’d not be as ideologically and historically entrenched in it as Putin to say no. An oligarch like him is highly opportunist.