we knew that https://www.washingtonpost.com/news/the-switch/wp/2016/03/30/lots-of-coders-are-self-taught-according-to-developer-survey/
People have been teaching themselves to code for decades, but the popularity of these overpriced boot camps are increasing. They only started springing up in large numbers a few years ago. I know that I wouldn't pay $4,000-10,000 to learn how to code when there are free websites that teach programming languages.
For a while I made a living programming in a sequence of languages. Fortran, C, Pascal, SAIL, C. Various scripting languages. The only course I learned in college before using it at work was Cobol. Which is not in the list above as I never did use Cobol at work.
I think it was John McAfee that said the best coders aren't taught, they are people that had natural ability and picked it up on their own. He also said that is why the government will never have good cyber security. The government would hire a person with a clean background and the right degree rather than the kid with the mohawk that smokes weed all day while working.
The federal government actually hires people like this all the time. They tried to recruit one of the students in my PhD program who has a criminal record for hacking. Her degrees are in anthropology and criminal justice, so she's self-taught.