I used to do a spin class with an 82-year-old guy who told me that his performance level stayed pretty high until he hit 77 or so, when his recovery times started getting longer. He was 30 years my senior and still easily outperforming me.
If I can't make it without help, I will get an e-bike, no hesitation. If I cannot handle roads, I will ride MUPs. If I cannot balance, I will get an e-trike.
So long as I enjoy riding ... why not?