I have a (unsupported, unsubstantiated) theory that YT detects phones of "sleepers" and pushes more profitable content with the understanding it won't be skipped.
I've got a few spare phones, maybe I'll run an experiment.
You can have multiple YT accounts on a single gmail acct, but I don't think that'll fool them. They know where you initially logged in from. So you will likely need multiple gmail accounts to do this kind of experiment.
They don't have SIMs, they'll be connected to a VPN router, and I'll create new Gmail accounts for each device, from each device.
It could just as well be something super valuable -- like an unattended kiosk device playing youtube to a crowd of people.
Someone who falls asleep watching YouTube will skip ads, unless they're asleep.
The idea is that if YT can infer that someone is asleep (location, no movement, no sound, low light, night) that they can show the longest, most skip-inducing ads that they've got since they know they won't be skipped.
The difference between the kiosk and the sleeper is that if the sleeper gets a 20 minute ad at 2pm while they're eating lunch, they'll skip it. YT is incentivized to show the most profitable ad that someone won't skip.
The value in identifying sleepers isnt showing a long ad, it's showing a long ad with the certainty that it won't be skipped.
Because YouTube has a functional monopoly on online video advertising in a huge number of markets.
Enshitification is not just for YouTube's viewers and creators.