That issue is trivial to solve. We simply stop wasting so much labor. Labor has been cheap for a long time. That's resulted in companies using it very inefficiently. Think of all those office workers that lose half their day to pointless unproductive meetings that could have been an email. Companies can only exist with such comically inefficient practices because labor is cheap.

Higher labor costs will encourage them to use labor more efficiently. The total economic output need not decrease. There will still be plenty of resources available to take care of the elderly. We'll just stop wasting so much labor.

Except we do have ai and robots now. This isn’t every other generation in history, we are dealing with gigantic changes. That said, we need better standards about when to end lives. Everyone shouldn’t be kept alive forever. It’s not healthy or natural. My grandparents all died in nursing homes at like 100. Their quality of life was shit. That’s not how to deal with the problem of aging.