I started my Saas business in my 30s and ultimately it has been enough for me to be financially free. I’ve run it full time since 2005. Yes, I’m in my 50s now and still running a saas and developing new software. 30s, yes you can start over, and it’s even still young to do so.
Edit: I was not a software developer professionally before I started over.
I guess I'm one of those bad programmers who does "weird things" , I often create a string with my entire page and then output it. I thought it made more sense since I now have a string that I can run regexes on or find/replace if necessary. Also it makes it easy if I decide I want to cache the page somewhere, I think I must be "dumb and gets things done."