for the benefit of doubt, i'll let the phone recharge and test again tomorrow
otherwise i'll take a slow mo video and let you guys judge but it is very apparent that the animation smoothness is significantly better on mate 20 especially when you use both phones side by side
i think its something like lcd vs led, seeing a lcd by itself the screen is great and the colors are all great
seeing a led alone also gives the same results, great but not better than lcd
it is only when you put a led beside the lcd, you'll see that the difference is actually drastic
when using the iphone alone, i don't really notice the jutter unless i go looking for it but using the iphone 11 beside the mate 20, there is almost a night and day difference
its like when you play a game at 28 fps, that's the iphone.
on the mate 20, the game runs at 60fps, nothing wrong with it
edit:
i've checked online to find if others find androids to be more smooth than iphone and i found this article
https://www.phonearena.com/news/Android-can-never-be-as-smooth-as-iOS-myth-busted_id26252
perhaps it is true that android can be more smooth than iphone and my eyes are not playing tricks on me