> Unless there is convincing data otherwise it would still be a filter for wealth. If a college degree provides opportunity then the wealthy will arrange for their children to have college degrees.

As a counterexample: Dutch universities can’t select for students (for most studies), and annual fees are ~€2k annually (regulated). There will be some bias towards wealthier backgrounds that are more able to invest that money and time, but compared to the US/UK systems I expect it is minimal.

This is not unique, I think systems in the Nordics and Germany similar.