The bug:

Even if they are named, they despawn.

However, villagers, iron golems, and mobs with  items did not despawn.

Steps to reproduce:

1. summon a mob (that follows the normal despawn rules)
2.  name it and surround it to prevent it from escaping.
3.  leave at least 128 blocks away and come back.

Observed Behavior:

Despawns even when named.

Expected behavior:

Does not despawn with name attached.

Video:

https://drive.google.com/file/d/1DhD8ebCACRjOmb8latnR120Rkt5QUKhT/view?usp=sharing