It's not quite the same because the admission system is not random. The grandparent commenter was concerned that 'people who go to college' may have better out

It's not quite the same because the admission system is not random. The grandparent commenter was concerned that 'people who go to college' may have better outcomes not because of college but because they are smarter or wealthier. In Scotland's case the admission is based on grades so it still leaves open the possibility that college graduates are just smarter than everyone else instead of better educated.