Oh yes, that is very true. I guess I am a little bitter because for 40 years I have been wanting to make music and I fell for this idea that if you learn an instrument classically and learn to read music then it will open every door to every style.
Hmmm… that was my approach too, but I am now at the age where memorised very quickly becomes forgotten. That might also be why I am finding improvising much more appealing. 
If you learn how music works you don’t need to memorize a bunch of songs to play with other musicians. Most songs follow a pattern and usually are in 1 key. This is the key to learning songs on the fly.
Age should not cause inability to remember by itself. Keep in mind that I am a neurologist, so this is what I do. If you really have a memory problem, please have it evaluated. There are a lot of things in life that get in the way of memory, but there is also scary stuff.
My goal is to learn a bunch of songs before dementia sets in so I can still play them and annoy my nursing home friends.
Yes, but this is not my goal. Jamming is fun and I do want to do some of that, but mostly I want to play pieces that I enjoy for myself and those around me (see above😜).
I’m going to add a bit of a wildcard here now, I’ve learned a lot more about music since a while ago when I decided that I wanted to stop playing other people’s music (well not entirely!).
I’ve found that removing preconceived ideas has removed any restrictions of what I do, I have experimented a lot with ideas involving dissonance and odd time signatures and time signature shifts; OK some of it sounds pretty weird but it’s creative and still very satisfying because it’s exploration and elimination of ideas that don’t really work; all of this also doesn’t really involve any notation requirements.
I have a little idea I’m working on at the moment of applying a completely different musician’s style to a particular piece where the styles in theory shouldn’t work very well.
To sum things up, I’ve put the fun back into what I’m doing and also adding a lot of interest that’s giving me inspiration to play again.
That is awesome, Darrell! Finding the inspiration and joy is what it is about.
I fantasize about being so creative, and maybe someday I will turn in that direction. However, I have nearly 6 decades of experience that this is not my strong suit so I am not basing my personal goals in that direction.
Fortunately I find inspiration in learning pre-crafted music and playing it, so far anyway.