Yes, the input latency of the Bedrock Edition of the game.
As far as I am concerned, this highly degrades the Gameplay experience and overall responsiveness. Giving this a look and fixing it might resolve thousands of reports on this issue and prevent creation of thousands of new ones when this escalates.
A trace-down of the issue:
Most sources say it was around 1.16.200 when the bug has aroused.
Most likely related to full implementation of Render Dragon for PCs and mobile devices in that version.
It seems that each new version of the game is escalating this issue to be worse, especially with the development of Vibrant Visuals.
Steps to reproduce the issue:
Join either a world or a server
Move your mouse or swipe your finger
Check the delay between input and action, compare it to Minecraft: Java Edition
Expected result:
Client camera rotates in a timely fashion―below 25 milliseconds or 0.5 ticks, excluding monitor's scaler chip latency.
Actual result:
Client camera does not rotate in a timely fashion―it can take from 1 (for a high-end gaming PC setup) up to 4 in-game ticks (for a slower device like an XBOX ONE), for the camera rotation to be displayed on screen, excluding monitor's scaler chip latency.
Could prevent Java Edition players to play Bedrock Edition again. Yes, as a Java Edition player myself, this is little to unplayable as I am used to low input latency I get on Java.
This issue is being tracked at MCPE-186474.