When the villagers are pushed out they act like they are moving on their own but they are still sleeping.
Sometimes the mobs freeze for a bit and then come back.
Do the ghost mobs drop anything?
This also seems fixed in the 1.16.100 release.
The ghost mobs ARE invulnerable. I was in a raid when one of the vindicators froze and still attacked me and I could not hit it back.
Reopen this bug, getting the same issue on both 1.20.81 and the latest beta version on my Google Pixel 7a