This is happening because all platforms are optimising for the one single metric that matters most to them - engagement.

When you consider all users as a whole, the way to get engagement is not to have a good UX that lets you tailor what you see and search for the specific things you are interested in. The way to get it is to shove a constantly changing and brightly coloured stream of “content” right in people’s faces where they don’t have to do any thinking or make any decisions, they just mindlessly click what is offered and consume.

From Netflix’s perspective, they want someone to go from opening the app to watching a video in 10 seconds, and if they don’t achieve that, it’s a failure which they will optimise away.