Why can't King of Glory Android and Apple add friends with each other while QQ Speed mobile games do it?

As a classic character battle mobile game, "Honor of Kings" has been loved by many players since it was launched. However, due to the limitations of different systems, the two cannot add friends to each other. What is the reason?

The Apple system and the Android system have been two opposing systems since ancient times, and there is a competitive relationship, so the data in the game cannot be interconnected, so it is impossible to add friends, and it is also impossible to be a disciple or give gold coins.

In addition, WeChat players on QQ Speed Apple system can only play with WeChat players on Android system or be both QQ friends.

And Apple and Android players can only add QQ friends or WeChat friends, but the account data is not interoperable!

QQ Speed can at least add the same team to Android and Apple players. It would be great if Honor of Kings could do this.