Player can only retain swimming position on Y=1

Steps to Reproduce:

1. Create a pool of water above Y=0;
2. Stand at the bottom;
3. Start swimming downwards and release the walking button:
   You stay in the swimming pose until you move vertically, either by pressing the ascend button or looking up.
4. Get up, Try the same thing on any other height.

Observed Results:
You're unable to keep the swimming position on other heights.

Expected Resuts:
You keep the swimming position as long as you're not moving vertically anywhere in the world, similar to Java Edition.

Screenshots/Videos Attached: Yes

Notes: