The only thing I've ever regretted in my life is not going and doing a startup right out of high-school. In hind sight I already know it failed, but I still regret it. School will always be there IMHO.
Maybe it's a 'the grass is greener' kind of thing. Though I did have the same mindset that "school will always be there." I just never quite made it back to "there."
(My response might be a but jumbled, but I am agreeing with you, while at the same time looking back on my own thoughts and feelings of past decisions. Sorry for any confusion.)