Eyes of the players are too high while crouching, the eyes aren't on the center of the head (due to MC-48191).
Its correlation to the height of the hitbox doesn't match that of a standing player.
MC-142684
Player's eye height is slightly offset while crouching
Open
5
Kezk
(Unassigned)
Confirmed
Hitboxes
Minecraft 1.13.2, 20w13b, 20w51a, 1.16.5, 1.18.2
Retrieved
Can confirm in 20w51a.