It's not. The vast majority of worthwhile, well-paying jobs require significant education and/training after high school. Not because it's a credential game, but because society and work are complex. And it's getting more complex, not less.
--
I'll also risk the opinion that there is more to life than work, and higher education has advantages for people far beyond their ability out-compete one another for corporate jobs. And I would argue, for society as a whole.