From my personal experience native YouTube app on my TV is awful and laggy, I assume because my TV is underpowered. I would assume most are though. If it's that big a part of their revenue I would expect it to be a little more optimized though.
Related:
More users are watching YouTube on TV than mobile
Maybe we can get rid of terrible vertical videos then.
What user agents are commonly used from TVs?
I wonder what the breakdown of this is with active watchers vs restaurants/businesses that just have like a youtube playlist or live stream on constantly as a source for audio or background entertainment. I know personally that my dentist, barber and a few different takeout places around me do that.
Also curious that shorts are popular on TV? Maybe it's kids or people without a dedicated device using smart TV features or a console to watch?