BEC is one of the best YouTube channels. Not per se because of the legos, but in how the videos assess and iterate. Also, as another HN commentator pointed out, its not "baity", (s?)he doesn't do any of the stupid BS to hype him(her?)self.

Yes, I'm in the target audience: middle age male in US.

I think this is the perfect example of a niche area with an whale/long-tail distribution. It demonstrates the futility - to me - of doing any serious "YouTubing" as a professional plan - its something you have to strike luck and then build on.