I was able to replicate in 1.7.2 → 1.16.2 (Singleplayer, /summon was added in 1.7.2)
I was able to find a workaround for my motion issue, I made the eye of ender ride an armor stand.
(Tags are use to kill the armor stand when the eye of ender of ender destroy itself)
/summon armor_stand ~ ~1 ~ {Tags:[A],NoGravity:1b,Marker:1b,Invisible:1b,Passengers:[{id:eye_of_ender}]}
Can confirm for 21w19a
Here's a video demonstrating the issue: https://youtu.be/SB9lBc0GhXw