I don't even think Khan Academy's original teaching revolution quite panned out.
I still remember when Khan Academy first came out, there was talk that teachers would go obsolete because teaching would become centralized and delivered over video.
Khan Academy to me is still just a YouTube channel trying very hard to be something more.
Indeed, reverse classroom, everybody getting access to high quality content, video then interaction, learning paths, etc.
Well, in practice it's still about the amount of time a pupil does train with the right oversight and that is precisely the bottleneck that hasn't been alleviated.
Well it wasn't really a teaching revolution. It was a marketing job around a YouTube channel that purported to be a teaching revolution.
The thing is people want more than material. They want the material to be accredited and examined. Otherwise there is no demonstrable credibility from doing it.
And there's a whole world out there of higher quality material with has that accreditation and examination structure around it. And it existed, sometimes for decades in the case of The Open University, before Khan Academy appeared. But it costs money.