I just turned 53 and can comment on this...
First off, Capt JR, you posted this at 6:59 am. Real pool players don't even know that hour--except when it is the LAST part of the "day." Your getting up this early means you weren't out playing your heart out until closing time, right?
And, besides the getting up early thingy, you have other hobbies, like your piano playing. And I bet you're committed to some family things, and you have a job, etc. These all interfere with getting better.
All that aside, I'd say ANYONE can get better at any age. The problem is the NET increase in better. While I'm getting better at strategy, for example, my physical limitations are growing: bad back, eyes, muscle twitches, etc. Now add boredom, lack of desire, been-there-done-that paradigm, other thoughts, etc. and getting better requires much more work than when younger. But, to me, that is the fun in pool: overcoming NEW problems as they arise. This makes the game infinite to me, something I like.
My best days are ahead of me.
Jeff Livingston