You said Owner NBT is fixed for entities (works even after a certain period of time).
well, data modifying an arrow's OwnerUUIDLeast/Most and setting it from a player's UUIDLeast/Most doesn't work. (for summoned arrows)
Please, I need help in this. My datapack requires this
I'm pretty sure it's related to it not working after a certain period of time since arrows take 1200 ticks to despawn as far as I've seen.
Modifying NBT data during the lifetime of an entity is not supported.
See also MC-69821.