But college education does have value for most people beyond signalling. Whether it's worth $80K-$100K (depending on your state) I think is a harder question, but I definitely think it's >>$0.
I think the reason for this is hindsight bias, we don't realize how dumb we were before college vs. after college. Maybe going to an expensive day care where you are spoonfed super basic math and sociology or whatever is not valuable. But what I do think was valuable for me when I graduated 5-6 years ago from a state U.S. school was
(1) learning to talk with other people in a professional way,
(2) dedicating yourself for 4 years to studying one thing and becoming generally knowledgeable and mature about that subject, so that very little can surprise you, and
(3) learning self control and independence, and also how to drink/use drugs without embarrassing yourself. Valuable professional skill especially in tech.
I don't think (2) can be accomplished unless you take the initiative to go beyond the basic requirements for the undergrad curriculum. At least in math/CS, which is what I studied. But in industry, that maturity comes in handy especially as you're given loosely scoped tasks and you have to determine what's possible or impossible and then convince various manager types from foreign countries who are pushing back and sometimes threatening you. And as your peers whine and are weeded out, you see more and more how valuable that maturity is.
Most people don't even believe that becoming more educated makes you "smarter". "Smart" is this CPU clock speed you naturally have and then "education" is running the cpu through various benchmarks.
School is just standardization of the benchmarks so it can't be cheap and freely available. We don't want everyone to join the guild. As a society we want joining the guild to be as prohibitively expensive as possible while pretending we wish the guild could be open and free. All a racket and bullshit for 99% of the population.