That seems to imply that they singlehandedly (or fivehandedly) exhausted the promising pool and kept it dry since! But that's not the case, right? So whatever they did - while definitely important at the margin does not completely change the bulk of the market.
We can look at their employment numbers, they did not hire millions of people, yet there are millions of capable juniors globally eager to jump head-first into software development.
Bootcamps closed because hiring slowed down. (Because ZIRP ended, everyone doubted that the Fed can do a soft landing, and on top of that the certified bubble of AI-mania meant that companies increased spending on buzzword driven development, and ... on top of all this increasing cloud costs and slowing growth meant that no one felt the need to hire juniors.)
Oh, and of course due to the amazing tech demos where this or that LLM created a site/game in React in a few minutes, or even issued a PR, the meme of end of coding led to a pretty significant belief about the end of juniors.
Not before FAANG hired the promising juniors first, FAANG are very willing to give on the job training. Or at least were a couple of years ago.