So, if a CS degree is overrated
Which it is to some extent (I say that as a CS major).
I did find it useful and still find many of the concepts useful, plus I really enjoyed the courses. But the degree to which CS majors seem worshiped seems overmuch, or at least the degree to which non-CS majors are thought not to have the same skills seems overwrought. Non-CS majors can easily learn the aspects of CS that make a CS degree useful and give you a real-world advantage in the workplace. Think on it, what aspects of a CS degree are not able to be learned outside of college?
why isn't college in general overrated?
It is vastly overrated. If I were at an age to go to college today, I would elect to spend four years focusing self-study on a primary topic along with some kind of apprenticeship approach, or perhaps deep contribution to a set of open-source projects.
You could easily add in other aspects of study for rounding and spend vastly less than you would on a "real" college. Get a dirt cheap apartment around a college of your choice and you can enjoy all the social benefits with none of the massive debt.
why isn't high school overrated?
Public high school is not overrated, because the ratings are already horrendous. It certainly is not worth much currently, it serves mainly as a way to keep most kids off the streets for a number of hours per day. Far better to either go to a private school, some kind of charter school, or be homeschooled.
What you're saying is that education is pointless,
The actual thing he was saying is that EDUCATION is valuable, but you are only getting a real education to varying degrees from each of the steps you outlined.