Building Terrain when joining a realm

When I try to connect to this realm, I'm locked in the Building Terrain screen.

I have updated the game to the current version (1.16.221)
I have uninstalled and reinstalled the game.
I have disabled all resource packs.
I have restarted my computer.
The owner has closed and opened the realm.
The owner has made a copy of the world save, and replaced the original world save.

Joining servers works just fine. It's just that particular realm.