Yes, I am aware carrier can control carrier/network settings since those are loaded from network anyway, you can try to override them, but obviously if it's something like Cell Broadcast, call forwarding/barring or caller ID and others, carrier can decide to use different settingh from yours.

I feel like you are confusing local Android settings with carrier settings loaded from network. For instance carrier is not going to change setting of your default keyboard or ringtone without (carrier customized) system update.