If you had a couple of hours with Paul McCartney teaching you how to play a guitar you wouldn't want to waste time getting him to teach you how to tune it. If you had a few hours with Da Vinci you wouldn't want him to spend the first half an hour on mixing paint. The same is true for all the Masterclass courses. If I could spend some time with a world-renowned expert in anything I don't want them to waste time teaching me the basics. I can get that anywhere. I want to know the thing that elevates them above everyone else.
Most photography courses have the opposite problem. When a course is basically "Learn what an F stop is and use the rule of thirds for everything and then you'll be an amazing photographer!" it's often not teaching people what they want to know. People already know how to use their camera. When you pay money to take a photography course you want to know how to compose an incredible picture.
Masterclass is not about teaching people the basics. The expectation is that students are already knowledgable to some extent, want to become a master at their chosen skill, and want to learn from people who have perfected it.