I didn't save the message it sent, but I heard some people complaining on main and saw someone respond to their complaints about Gravity Errors during WoE by saying that they thought it had something to do with fish. I had not had a Gravity Error in over a month until I started using fish two days ago. Here's my observations:
I used fish normally with no error whatsoever, but then I tried to take Fish to Amatsu Level 1 w/ Firelocks. I would teleport around heal-bombing the firelocks and when my SP was low I would eat a bunch of trout. Then I would teleport again - everything fine. However, if I had two back-to-back teleports I ALWAYS got the gravity error as I selected "Random Location" from the teleport menu.
I never got it any other time, and I've only ever gotten such an error while using/carrying trout (maybe any fish? don't know - haven't tested). I'm not writing this to complain, just trying to help single out situations in which fish might cause Gravity Errors to try to help you guys out. If you already knew about this particular situation, I apologize for wasting time.