I used to go to school with a guy who dropped out of school at 15, having failed year 11, get a job working outside, did a part-time course, ended up in an apprenticeship, worked a few years, started his own business, sold it, he's 28 now and owns his own house without a mortgage...
Put him in front of a computer and the most he can do is use facebook and play video games.
That's a single case, but there's millions of people just like him, and there's millions of people who are missing out on having a good life because we told them they aren't intelligent enough to go to university simply because they weren't good at one thing at school.
People who are successful despite being uneducated are outliers. Stories like OP (and Bill Gates and countless others) are stories. Anecdotes. Single data points that are meaningless without context. Deciding to forego an education based on such stories is a risky game.
While I totally agree that the schooling system is outdated and primarily a way to socialize children, what programmers tend to forget is that we have a very special profession that has both low barriers of entry and high pay. Literally anyone who has access to a computer can learn to program. This is not the case in most professions! While aspiring programmers can tinker around with Linux in their spare time, an aspiring doctor can't tinker with a cadaver without being in school. As programmers we are extremely lucky that all the tools we could ever need are free and on the web.