Kajo
It’s because google has effectively unlimited resources and first-adopter advantage combined. The people who originally made youtube in 2005 would have never made money from it, even though the max upload quality was 240p (I remember when 480 on youtube was still considered high quality lol). But they got an audience which is what mattered. When google bought them, they still couldn’t make money, but they could prevent ANYONE else making money with a similar product but throwing enough money and creator-focused policy around to make any other platform look just plain stupid. Even today, how much do you think it costs to store and serve the hundreds of thousands of videos uploaded to YT a DAY? Many of them at 4K res or even 4K60hz??? It’s a massive undertaking and nobody can afford to build a competitor. And without youtube, the internet would be a much much smaller place.