Well, the point of college isn't to do job training. There are trade skills for that. College exists in the exact state high school did before it was made free for everyone. It is a barrier for entry into "good" jobs and the middle-upper class. It is simultaneously a way for people to learn and become informed citizens, to get some context for the world around them and how it operates, to learn economics and philosophy and mathematics and physics and computer science if they are interested in it.

After a while we said "no, everybody should go to high school and learn civics and math even though they aren't necessary for most specific jobs". Before that, we had the poor starting manual labor or apprenticeships at 12, never learning anything beyond their specific skill, while actually becoming educated and a citizen was reserved only for the rich. We decided to make our workforce and citizenry more thoughtful and educated and improved society as a whole significantly.

It's time to do it again. Our world is much more complicated now, human knowledge has expanded vastly. College education is now the baseline for 'educated person' and that's okay. It's great, even. Thanks to free high school the poor can study math and history. If there were free college, the poor could study economics and philosophy and computer science too.

How many talented people do we lose by shunting the poor (who are, in capitalism, always the vast majority of the population) into non-education job training when they are young because they can't afford to learn about the world?