When you ride a very fast minecart after a while you'll get frozen in place. You won't be able to move your camera properly and won't be able to exit the minecart. The only way to get yourself unstuck is reloading the world or using commands to die.
The internal server is still running fine and the game doesn't crash in any way, but the chunk will just never load.

Note: The reproduction world has a datapack to give it a 4000 block build height limit but that's just because that's the most efficient way I could make a reproduction setup.
Making a long line in a regular world takes several minutes with commands and the world would be too big to upload.

This can be reproduced in a regular world as well.

Reproduction Steps (If your PC is too good you might be unable to reproduce this but idk)

• Lower your render distance to 2 chunks (the lower your render distance the more likely this is to happen)
• Use this world REPO.zip (Warning: Make sure you have at least 4gb ram allocated or you might face extreme lag)
• Teleport to the top of the track
• Ride down

Observed Result

• You get permanently stuck "waiting for chunk"
  

Expected Result

• The chunk would eventually load and you would resume travel once it does.