Closing World While Riding Nautilus Causes Invalid Player Data Error on Relaunch

Steps to reproduce:

1. Create a world in the 25w41a snapshot

2. Tame a nautilus and give it a saddle

3. Ride the nautilus

4. Close the world while still riding the nautilus

5. Attempt to re-open the world

Expected Result:

The world would re-open

Actual Result:

After loading terrain you receive an error saying Connection Lost Invalid player data