Almost every child I've seen in the past 5 years has had YouTube in their hands.
I would expect all their data points to the idea they should suggest the same video over and over again.
I've also noticed the infants of my friends don't know how and have no interest in skipping the ads.
So long as Google can continue to plausibly claim it's women in their 30s-40s watching the nursery rhyme video (because that's who's logged in), they can continue to rake in the more expensive advertising associated with that demographic.
That stops working when the advertisers realize they aren’t making any sales from those ads.
But honestly, the moment they decide to make arbitrary decisions about what videos should be played next they are going to make some miscalculations. Some times they just made worst calculations than average.
I wouldn't make that assumption. Personally, I have a wide range of musical genres that I listen to and those tastes change over time, even month to month depending on how I'm feeling. I've met enough people that say similar things to think this isn't uncommon.
It seems they're trying to play it safe by strictly showing the same thing you just watched. The bias seems to be heavily towards your recent watch history. You can actually see this in action if you go through your subscribed channels and watch a few videos from channels that you haven't visited recently. The change to your feed is immediately apparent.
I've also noticed that they seem to have blacklisted or at least severely downranked some channels even when you are subscribed so they rarely show up in recommendations. These aren't even controversial channels but they don't squarely fit into a category either. Overall it feels like they've shackled a previously good recommendation engine in order to appease their loud critics. I'm really hoping someone can create a viable competitor soon, I'll abandon YouTube in a heartbeat once there's another option.