I think age limits are an option but are not really going after the root of the problem, nor are they a good solution. Our arguments that the elderly can't represent the youth can be made the other way just the same.

One one end, the districts are too large, so you end up with the shit show we have. You don't end up with local communities voting on who reflects that community best. It squeezes out any opportunity for third parties.

Secondly (Don't get attached to the people in this, the argument carries to any party/district), the democratic party will not allow AOC to run for Schumer's post. There's no supported way to ask the electorate if they would like a changing of the guard. Suggesting to primary someone who has been as successful as Schumer or McConnell would be political suicide. So you're stuck voting for Schumer/McConnell, even if you would prefer the youth candidate... in the NY example, Schumer still gets the votes and the party keeps supporting him. It's a blue seat and that matters more than getting "accurate" representation. I'd push for doing ranked choice primaries for all federal positions.

TL;DR -- smaller districts. New parties. Encourage (or mandate?) primaries against incumbents.