I too am an old man, at 71, and even though I've played on and off since I was 18, I've learned more in the last two years than I did in the many preceding years. Two ingredients that I did not have before: 1) unlimited time to practice, and 2) a world of online instructional material, via YouTube, online teachers, plus the many members of TalkBass who provide tips, and ideas about technique. Oh, and equipment is much better now too.
I look forward to seeing your posts on the board. Welcome.