All these really old people still in politics, is the power really that intoxicating, is the job that easy? Pelosi, Biden, Mitch et al.
Why would us "normal" people rather sit back on the beach, but they feel the need to keep running our lives until they drop dead like Ginsberg.
Possibly "true believers", but more likely they have no actual marketable skill, need to maintain access to political power to avoid arrest for all their prior crimes, and they have grown accustomed to the lifestyle that they can only support through bribes, insider trading and other forms of graft and corruption.
They don't need skills, they are already rich. Pretty sure they will all die with more money in the bank than they could ever spend. And I don't think they are at any risk of getting arrested. Whoever takes over their jobs will want to get rich doing the same thing so would cover for them.