If you knew as much as the high-school grad from 1965, you would still do OK today.
There is a very expensive assisted living facility near me. A very substantial fraction of the residents have a high school degree only. Our businesses used to recognize bright, hard-working people, train them on the job, and let them move up.
I graduated from high school in 1963, from a small town school where most of the parents worked in trades, declining factories, or small businesses. There was no push to go college, and even that for all but a handful was the then very inexpensive nearby state college.
The big difference back then, in that environment, it was assumed that nobody would leave high school without a job skill. The guys all took serious vocational courses. The college bound took a one-year combined course of shorthand, typing, basic book keeping. The non-college bound girls took business courses and home economics. Everyone took an economics course that involved budgeting, running a small business, basic economic principles. Guidance didn't direct anyone to colleges they and their parents couldn't afford.
I look at that list of things that prepared us for the future, and NOT ONE of them is in the contemporary high school curriculum.
You can’t tell theses people that a High School education 40-50 years ago was equivalent to and in most cases far superior than most 4 year College Education’s today. It will destroy their highly coveted Self Esteem. Let them be Proud Morons, they like it that way.
I am constantly chatting with degreed Millenials who display gaps in their knowledge of the world that was all stuff I had learned by the eighth grade.