30 second despawn immunity is broken again

Non-persistent mobs are supposed to have 30 seconds of despawn immunity after spawning or taking damage. This is once again not working, like in 1.18.10 through 1.18.31 (MCPE-152500).

Steps to reproduce

1. Open the test world from MCPE-152500. It is a flat world set to simulation distance 4 with two platforms 32 blocks apart.
2. Stand on the blocks at X = -1, Y = 100 and watch the platform at X = 32, Y = 100.
3. When a monster spawns, start a stopwatch and watch the monster until it despawns.
4. Repeat steps (1) - (2), then when a mob spawns fly over and hit it and start a stopwatch, then fly back to the X = -1 platform and watch the mob.

Expected results

Mobs would never despawn sooner than 30s after spawning or 30s after taking damage.

Observed results

Mobs sometimes despawn sooner than 30s after spawning or after taking damage.