When moving from game to game, whether that being leaving an existing one or entering a new one, much of the time the game with get stuck on ‘Loading Resources’. This screen does not go away, meaning that Minecraft will have to be restarted entirely. I have found that it happens about every 5 - 10 games. I don’t think this is game-specific.
Platforms / Version:
I have encountered this on Phone, iPad, and Windows 10, on multiple accounts. This is on the latest (v1.16.210) update, but I have experienced it for a while now on other updates. Other people that I have spoken to/know also experience this bug quite consistently.