I have the same problem.
I used a custom block addon that defines a number-type array in its block states, and when trying to join the world from a different platform (e.g., iOS or Android) with the same addon installed, the other device cannot connect.
Using boolean or string types in block states does not cause this issue.
Same thing happened to me but I can’t even log in or log out
Happens to me as well on elementary OS 5.1 Hera
GPU: Intel HD Graphics 4400
Driver: i915
RIP the best redstone feature in making deadly, compact traps; compact BUDs; etc... 😞
Can also be confirmed on 1.21.11