Edit: also some parts of the world, like the US and UK, have district-based voting systems that favour large parties. You can't actually get anywhere in politics without the backing of such a party, and it would be difficult to convince the party to make you a candidate when you aren't playing the same political games.
The big time early years have massive rewards. One in a handful go on to be the team coach / manager. A few more graduate to coaching support staff at a much lower salary. A very lucky few land a job for life at ESPN or BBC Sport. Some don’t need the money. Some do.
The majority move on though and retrain as gym coaches, teachers, parents, therapists, firefighters. They take a pay cut and a role with much lower global impact and a much higher local impact. Often because the latter is genuinely very rewarding.
It’s something to look forward to as you get older but a drop in salary is going to be a fact of life unless you have exceptional transferable skills that put you at the top of the game in your chosen second career, be that in the private or public sector.
I can't imagine how this would ever become the norm, unless your early career is in crazy SV startup world or some similar environment, where VC funding leads to hugely inflated salaries but ageism is rampant. And if you do go into that environment but you haven't then earned enough to retire and/or learned enough to start your own business by the time the gravy train runs out, you're probably doing something wrong.
That might be their official salary (I'm assuming?) but unless senior politicians in the US are different to almost everywhere else, that will likely only represent a proportion of their total income as a result of their political career. Between the perks that come with the job while it's happening and the consultancies and board positions and speaking engagements that come afterwards or even during, a politician who reaches that kind of level is probably going to make far more money from it than just their salary.
...and except for media celebs are usually not in the public limelight. Being in the public limelight frequently stinks.
There are few professions where those in the upper levels can command the kind of auxiliary income that a high profile former politician can. Even in fields like tech, it's not usually the case except for in the US.
If you want the top 500 people at benefiting you, and only people like you, and making sure that society as a whole doesn't benefit, even by preserving the planet for them ... yeah, sure, pay oodles.
"anyone who is capable of getting themselves made President should on no account be allowed to do the job."
Do you want a pay cut? I don't want a pay cut. Unless we take a pay cut and go become a elected, it won't be people like us who are the next generation of life long politicians.