I was 40 before I ever saw a computer. At 45 I had written books on them. At 78 I teach computer animation. It depends on your market. If you choose to specialise and study your market well you can survive doing just about anything. My experience is that most degrees involve learning much of what you don't need or may never use. Pick your market firt then learn what you need to know, who you need to know, and how you need to apply it. You may find you even need a degree.

I've never attended university, or passed any exam of any sort other than a driving test which I took for the first time at 54. I did take up the guitar to learn bebop at 70 though, but that was after I won a film award at 68 but before I started gym classes at 72. At 78 I do find my mind declining, but that is because I find learning programming quite hard, though it appears from my acquaintances, not as hard as it is for the 30-somethings who have other things to do. My friends in the 70-80s write books, go scuba diving, play jazz, run companies. Some have degrees and some not. Those that have feel that it doesn't make much difference providing you are generally active and not too much concerned with what you are supposed to be doing and concentrate on what you want to do.