Even with education loans, some people can't afford it, because they have to support the family financially now and you lose that opportunity when you're at university.
We've gone from discussing the original point ("Filtering by college degrees is filtering by family wealth more than anything else" is a US centric view: yes or no?) to discussing the efficacy of state bursaries for college education. It's not an inconsequential topic, but it's not the original point anymore.
I don't think the posted is making any discussion of efficacy here, but is simply stating that there are people (non-US) who have to make the economic choice not to attend school, so filtering by degree even outside of the US is problematic.