If you see yourself improving the lives of people around you later in life, which is commendable and the right thing to do, you have to start now, while you are still in your prime years. If you leave it when you are older chances are you'll be just another John waiting in line for the next Black Friday.
I have, from drawing to music, from writing novels to doing programming projects on my free time.
It's not very fun, you aren't good at most of it and it's very frustrating. It's also very rewarding being able to overcome limitations and building up skills. But it's first and foremost very demanding. You can't expect someone that just got retired to suddenly spark in creative energy, even if they intimately wanted to do everything.
Maybe we agree that it's all work, but there are types of work that even though they're frustrating, they are also rewarding in specific ways that is interesting for those that retire.
I’ve gone through extended periods of unemployment (by choice, not in a stressful way) before, and it’s wonderful but by month 3 I’m always kinda over it.
Retirement for me will probably look pretty much the same as working except I won’t necessarily pick a job that pays well.