My high school had multiple levels of AP classes in most subjects. I had burned through all those by the end of my sophomore year in high school, so I would have had to go to a proper uni. Generally speaking, graduating really early is a pretty stupid idea for kids even if they are intellectually capable. I saw it ruin a couple friends of mine, and in one school district I was actually four grades ahead of where I normally would have been at my age so I do have a first-hand idea of the problems. (Thanks to semi-regular moving around the country, I ended up back in a "normal" class level -- different districts have different policies -- though I still ended up being a few grades ahead at the end anyway.) Much better to coast through and have time to spend on other things. I always aced my tests, I just never did any of the homework, so depending on the class and how the teacher broke down your final score, that netted me B's and C's in most classes. Excellent bang for the buck; maximum outcome with minimum effort.
Maybe you hadnt internalized the algorithm "get good grades, go to elite college, succeed in world"?
That algorithm is not efficient of either time or money; I chose a more optimal route of my own devising and have been far more successful than most of those who actually drank the KoolAid and followed your algorithm (including my father, who had an exceptional education). In real life, I've managed to excel at just about everything I've attempted, and I did it younger and faster because I didn't waste precious years on pursuits of dubious return.
I had my own esoteric interests - stuff like wargaming and reading National Review and Ayn Rand as a teenager - but that didnt stop me from turning my brain on in class.
A point you've apparently missed was that it had nothing to do with turning my brain on in class. There was nothing in class for me to turn my brain on for. My grades were strictly the result of not doing a lick of homework, though I always managed to ace the tests. I always knew the stuff, I just didn't do the work nominally required to "learn" the stuff, but a good percentage of your grade comes merely from doing the work at every sub-university school I've gone to.
One more anecdote:
One of the smartest guys I ever met in my life was during my short stint in the Army (I thought joining a high-speed combat unit would be a good experience, and it was, but not for the reasons I thought). He was trailer trash through-and-through, about my age at the time, a high school dropout with a GED and a penchant for dive bars who lived with his divorced mom in a nasty wife-beater trailer park. For all intents and purposes, he was the very stereotype of ignorant poor white trash.
Except that he was one of the most literate, intelligent, and lucid people I'd ever met. He was better read and obviously sharper than the vast majority of people who come out of good universities. Despite his appearances and his environment, he was one of those people that when you talked to him it became immediately apparent that he had a razor sharp mind that had been augmented with an extensive self-education. Would a university education benefited him? Probably, but it would only have been a secondary asset. I have no idea what he is doing today, but he had an entrepreneurial mind. Last I heard from him, he somehow managed to buy a bunch of "cheap" commercial properties up in Portland, Oregon just before that place really took off from all the Californians moving up there (he swore the place would be a gold mine), converted the places and made a mint.
It is worth noting that income distributions in the general population measure average people, and for those people college education helps. If you look at the population of people who have turned in exceptionally successful results, you get an entirely different picture of how important a formal or "elite" education actually is. Highly intelligent self-motivated people gain relatively little benefit from that kind of education in the big scheme of things. I have a college education, but I've never put it down on a resume or CV or anywhere else, as it is among the least important of the things I have done in my life and nobody ever cared.