Minecraft app on iPhone extremely "laggy" when on weak networks

If you attempt to open the Minecraft app when on a weak network (such as a cellular network), the app will become extremely "laggy". It will not allow any buttons to work and the app appears to be running at very low fps. A video displaying this behavior is attached below. I assume it is trying to connect to Mojang/Microsoft servers in the background but I don't understand why that makes this behavior occur. Enabling airplane mode on my device solves this problem, but I don't want to enable airplane mode just to play Minecraft (important text messages may not be seen, etc).

 

I'd appreciate a solution to this issue. Thank you.