Udemy always had that scammy vibe with courses "90% off" (from to $200 to $20 and things like that), plagiarism, as well as anti-patterns and very questionable quality control on the courses themselves.

They, unfortunately for some good sources like edX, managed to brute-force themselves into the mainstream, which is quite sad.

I remember some of the early days of "Into to AI" and courses like that, Udacity in early days (with courses from Steve Huffman, Peter Norvig, Sebastian Thurn) and how they managed to help me learn so many things.

I would be very surprised if people can say the same for today's array of options.