Why would someone do that? Especially for presidency which is the final stage of their career? They're not beholden to or reliant on anyone no more so shouldn't have to be swayed by any adverse interests.
They run from the left in order to get elected, that is the sham. They tell people things that people want to believe that they know they can't deliver in order to get elected.
Then they govern from the centre right status quo which aligns more with their actual beliefs.
A presidency lasts 8 years of your life, best case scenario. And the presidential salary will not make you rich. So, if your only goal is a good life, you have to use your presidency to get people to make you rich afterwards, which means favors for the wealthy.
