I think you attribute a causality where none necessarily exists. Some of "The Powerful" are indeed absolute bastards "always looking out for n.1", but a lot of them are sincere in their motives - it's just that they often happen to be ideologically misguided or forced into backfiring compromises by circumstances or greater powers.

Arguably, the most visible ones are often very sincere - because otherwise they couldn't sustain the drive necessary to reach certain heights.

I think it comes from the magic being dispelled. They are just ordinary people and they’re almost never well equipped to fill their functions in any meaningful way because of the complexity of the decisions they make.

There is a part of it about friendship, but it’s more because the world stops being black and white at those levels. Two politicians who come from the opposite sides will have more in common with each other than they will with any of the people who vote for them so it’s only natural that they remain faintly friendly with each other. They have to work together after all, as most things come down to compromises.