No one does video even remotely close to the scale YT does it. YT has by far the deepest market penetration (close to 3 billion monthly users), and has by far the most hosted content, and critically, youtube adds over a half-million hours of video a day.

Essentially, youtube adds more video every single day than the entirety of every other streaming service offers combined.

Youtube is in it's own category, and it's unsurprising no else wants to touch it.