You’d be better off posting this in the appropriate category not AIBU since it’s not an AIBU question and it’ll attract all the snarks.
Fwiw, I went back to college to do a foundation degree at 22 and felt old and ostracised but that probably had more to do with the course and the college than anything else. When I went to university the next year there was loads of 40+ 1st years and no one batted an eye. The majority had come through access courses.