"Yeah, one would think that both parties should come up with...

"Yeah, one would think that both parties should come up with some other better choices - younger, fitter and better educated"

Unfortunately candidates in the US 2-party system are completely reliant upon massive levels of funding.

The Dems will throw the coin behind their chosen candidate but will have no problem rigging the rules and circling the wagons against any popular/populist challenger e.g. Bernie twice and then Kennedy.

The GOP had a similar model but Trump was the ultimate 'black swan' candidate in that he had the popular message but also didn't need establishment fund-raising to win the primaries.

Hopefully 2028 sees the next generation take over, maybe Vance vs Newsom, but it's looking likely to be the battle of the pensioners,again, in November.