I was going through youtube when i saw this video:

https://youtube.com/yVFxnZDCFcY

This video was a test for the new ipad which supported 120 fps. Skip to 0:58 and you see the problem. This person haad vanilla textures on btw. The person sets the fps to 140 fps as you can see but when he measured the fps, it was capped at 60. He had also done a previous test of this ipad on 1.19.41 in this video:

https://youtube.com/JzD2ltFppqc

Skip to 1:19 of this video and the same issue comes with him adding that no matter what fps he set it to (even 10 fps) the game was capped at around 60 fps. He even tried to see if the same issue existed in his iphone which it did. The max framerate thing did not work.

I know this issue exists on any other platform because I have seen Android phone reviews with minecrafts tests. An example of one is this video:

https://youtube.com/fSWl6WHSTv0

Skip to 4:19 for the minecraft gameplay. At 4:24 he sets his render distance and sets his fps to unlimited and at 4:34 he shows his fps in which he is getting a constantly changing fps which shows the fps setter works on other devices. It is the iOS devices that have a problem.

I have even played on my ps4 to check this but the issue is not there.