I have been around a while, and have been into piano lessons about four different times in my long life. I have played off and on over the years, sometimes moving to living quarters where no piano was available.
I'm playing energetically now, finding that retirement gives me the luxury of practice when and how much I want. I have a nice mid-sized grand right in front of me here.
One might imagine a person would slow down at my age [64], but I do think I am playing better than I ever have. About the upper part of the "intermediate" range, I guess. I am not sure I have to "get better," because a very great amount of piano literature is within my reach right now. I will leave the "Transcendental Etudes" to younger, faster hands than mine.
One thing that has changed a lot. When I was a child I was worried about what my piano teacher would think. Now I only care what I think of what I am doing. No disrespect intended toward my teacher, but her role is to assist me in playing what I want, as well as I can. If she frowns or smiles, "too bad, too sad." I do get a lot from her, so I don't mean to seem to blow her off.
I don't know how long I will keep playing. As long as my eyes, hands, and mind are good, I suppose.