I was talking with my brother last night about online course platforms. I was arguing that there's plenty of graduate students or professors even in these times

I was talking with my brother last night about online course platforms. I was arguing that there's plenty of graduate students or professors even in these times that would have the time and skill to host virtual lectures/classes and teach from a standard textbook if the price was right. This is opposed to platforms like udemy which aren't known for their quality nor academic courses. But my brother argued that most inclined to make a course would prefer passive income from a prepared course. What are your thoughts on this? Personally I would pay a premium over udemy's already overpriced courses to learn how I would normally at university so long as I could attend live lecture conferences as needed if I needed to ask questions about the reading material or problem sets etc.