From what I can tell, it's a course that was mostly produced by someone else and will be delivered by someone else, but they recorded Mark Rober - the guy famous on YouTube for glitterbombing people - as the instructor. But their FAQ already states that he will "be able to" look at what students are doing and "may occasionally [..] give feedback", so most likely he won't be around to run the course.
Also, from watching the videos, I had the impression that the technical work is mostly done by other people, e.g. the famous glitterbomb was built by Sean Hodgins: https://www.youtube.com/watch?v=IpMxOmUcfOI
So first and foremost, it appears that Mark Rober is a great showman and a great narrator. Plus he's collaborating with people like Mr Beast who have the power of a skilled agency behind them (nightmedia.co) to produce just the right narrative to go viral. And his first videos appear to be sponsored by a marketing agency.
So I'm not surprised that this course is hyped up and not actually done by Mark Rober. I'd treat this more as a case study on how to perfect your social marketing ;)
That said, their core promise of building 3 own projects within 30 days sounds reasonable if they have skilled instructors running the course. And the price seems reasonable for such a learning experience. When I was younger, my dad built some technical projects with me. Over the course of a weekend, I would learn more about electrics and physics than in a year in school. And once you built something that actually works in the real world, you'll never go back to observing technology as a passive bystander. That attitude change alone might be worth the $250.
Plus, I believe Mark Rober to be a great showman. This course will likely be entertaining to watch, and paced just like a good movie.