I think the amount effort put into this goes way beyond gimmick. I only followed the first few episodes, but it was clear that he was very engaged with his audience, and that he put a great deal of emphasis on the educational value of the project.
You're right. I've watched many hours from the very beginning and this is about learning from the basics. It starts even before episode 1 with intro to C stuff. And he constantly reinforces the fact that this is for teaching "from scratch" and therefore isn't using libraries, but if you were to build a real game for sale there are places where you wouldn't be doing things the same way. Overall a very educational project.
Yeah I don't think that's a fair categorization at all. It's all free. And his dedication and commitment is to be commended. This is a free, multi-year, live training program that has been ongoing since 2014.
Yup, most game developers love sharing/talking about the craft. It's not an industry you join if you aren't passionate about the process of developing interactive content.