You have to understand that the average American functions off of lizard brain impulses. It would be probably go like this:
Acknowledging age concerns of the electorate = show of weakness.
Running someone fresh that appeals to this American Idol-esque popularity contest = show of weakness.
Running someone Republicans don’t have their talking-points fleshed out on = show of weakness.
America operates on principles of running someone strong who says they will always be strong and that if they ever become weak while in office and they acknowledge this to be replaced, the entire party goes with them like a tug boat latched to a sinking oil tanker. Trump didn’t win because he’s smart or a decent human being. He won because he exudes baseless confidence like a broken nuclear reactor exudes gamma radiation.
Democrats are so ego driven that they think death itself cannot claim them at a moment’s notice. I think this is part of the facade of the Democrats people are, unfortunately, going to respond to this election: Democrats, as a party, like to present themselves as being all about compromise and caring. Getting things done for the #AmericanPeople. But when it’s time to step down and let others shine in the limelight because you’ve had your time and the physical realities of age are something you have to acknowledge, or when there might be a better candidate for an election and you have to make the difficult choice of not getting what you want for the good of the country, that fucking sentiment disappears like a fart in the wind.