This is, effectively, no different than a carousel of algorithm-recommended content. However, UX studies have found users reluctant to watch something recommended to them. It requires making an affirmative decision on time investment. Most people have the experience of a friend recommending a movie or book and still being reluctant to dive in.
The problem is very similar to dating apps, if you think about it. This is why Tinder's innovation on "swipe left/right" took off the way it did. In UX terms it's better to drop users into something and make the cognitive effort be choosing to get out of it rather than choosing to get into it. It's a big part of why TikTok works.
The reason this isn't more common in video apps has more to do with UX norms at this point. Another important thing I learned about streaming at Disney was that no one really cares how innovative the browsing experience is. They just want to watch Frozen. They're used to carousels now, and they're easy to program. This, I think, speaks more to your sensibilities.
I typically share your mindset, but I can see the appeal. There was something nice about the TV that just, ya know, already had something going when you turned it on. I spent many happy evenings in hazy basement rooms enjoying whatever Adult Swim decided was going to be on the TV that night.
I chalk it up to overwhelming choices. Sometimes I just want to watch something but don't want to go through dozens of options and having decision anxiety.
Bonus is sometimes I discover something I never thought I would have liked.
This is by far the biggest annoyance with modern TV for me. If I've already decided on something I want to watch, it's obviously great to just be able to navigate to it and put it on on my schedule, to pause it, have no ads, etc.
But sometimes, for better or worse, I just want to plunk down on the couch and turn my brain off, and if I'm in that mode the last thing I want to do is try to find something worth watching on my own steam.
Like, Youtube is great! Yeah, there's a ton of crap, but there's so much on there that would entertain me and be a guilt-free, even edifying use of me time. But having to choose something new every 10-20 minutes? Actively managing a queue while watching stuff? That's - pardon my French - for the birds.
I used to do that but the shows repeat and at the top of the hour or sometimes multiple times they repeat the same news over and over. I get someone else might be tuning in and not have heard the latest news
Maybe there's some middle ground where instead of a stream it's on demand but continuous. So I go to videostream.npr.com and since it knows it's a single user it can push the news once and then just be shows.
That said, youtube autoplay is the basic concept, it just sucks at what it recommends.
I guess this is basically how TV worked in the pre-streaming days - the new episode of whatever hot series aired during the prime time slot, and lesser slots were filled with reruns / resyndicated stuff.
Good: I choose to when and what to change the channel to. The channel never stops.
Bad: YouTube video ends and I'm prompted to do something every 5 to 15 mins and even autoplay chooses to show me content from another channel.