[ndriscoll]

That's because they are not a platform for education. They are a platform for ads and encouraging hyperconsumerism. They merely allow educational material, sometimes. Expect more videos to be removed over time that don't align with their goals. e.g. I would not expect playlists of hour-long MIT lectures to stay there for the long term as the platform moves more toward shorts and algorithmic recommendations. Or their vast library of people's old random amateur videos that barely get any views/generate almost no revenue while costing them money.