@MojangSupport why is when yall update the game console players can join realms?

A Realm may not update to the latest version at the same time as your game. If you're the owner of the Realm and it still hasn't updated, please complete our request form at aka.ms/Minecraft-Support so our Realms specialists can quickly and safely assist with your question! ^IV

Its not my realm its a mates but im able to join on my pc so how come console players can't?