I have a theory that, wrt knowledge, the relative advantage of age has been at least partially eroded by rapid technological advancement. In traditional/tribal societies, prior to the 20th century, wisdom actually accumulated with age, because the pace of change was slower. Wisdom & knowledge could be passed on from generation to generation.
Now, wisdom and knowledge become obsolete quickly. Many things you knew 20 years ago are outdated. The ICE engine you learned how to fix as a kid is now computer controlled, or has been replaced by batteries. Your optimistic/open/friendly mindset now makes you easy pickings for online scammers. Hell, even your family's secret cherished muffin recipe is spurned by your grandchildren because it has gluten or they're vegan or keto or whatever.
All this is just a take, but when I look at voting patterns in particular, I find myself pessimistic that the elderly are wiser than average.