All I know is it worked for me. That's a conclusion based on reality. Sounds like it's you that's speaking from lifelong ignorance.
I have seen many individuals work full time and attend college. Some worked two jobs to afford private school tuition, others went to community college. The lucky ones were reimbursed by their employers.
Now whether going back to school is worth it in terms of dollars or job security, that's another question. They might have been better off financially becoming an electrician apprentice, a tree trimmer, or running for office.
Most people don't desire to be millionaires or movie stars. They basically want a house, car and their kids to do marginally better than they did.
That modest dream is becoming increasingly difficult.
Sure it did - in an alternate universe where everyone is you and has your circumstance in life, perhaps your fictional vision of things would work. But everyone doesn't have your circumstance, etc. You might as well set up a recursive "if" loop for a perfect world scenario and tell us how everything will work "if".