I don't mean to drag this conversation further off topic, but I can't agree with this. Relatively speaking, my iPad screen is far larger than my TV. It's not that I have a tiny TV. It's that most people forget to add viewing distance into the equation.
As a test the other night, I held my arms out about where I'd hold my iPad while watching and held them up to the TV. From the distance I was sitting, my 55" TV was a considerably smaller picture than if I'd been holding my iPad (honestly, it was about equivalent to holding my X in landscape orientation). It's still 55" vs. 10.5", but since the screen is significantly closer than my TV set, the end result is a much wider field of view on the smaller screen.
Granted, we're sitting too far from the main TV set, but the room layout dictates that more than anything else. My iPad, I can put as close or far away as feels comfortable. And since I have an earlier, crappier, non-HDR 4k TV, the argument could be made that I'm sitting in front of a superior screen as well. Especially since we're not sitting close enough to see the full benefits of a 4k picture with the naked eye.
Here's more information if you're curious:
https://www.rtings.com/tv/reviews/by-size/size-to-distance-relationship
To get slightly back on topic, I'd watch on my iPad, but never on my iPhone. And I love the screen on my X and prefer the more accurate calibration.