Why is GOS recommending 5G network bug 4G calling

In settings > network & internet > internet > carrier settings (cogwheel), GOS recommends 5G as network type but 4G calling. Why is that?

To my understanding, maintaining both 5G and 4G connection consumes more battery than just 5G or just 4G but maybe I'm misunderstanding something?

trilogy6202 Which works better for you?

trilogy6202 GrapheneOS isn't necessarily recommending 5G over 4G.

The 'recommended' label with 5G comes upstream from AOSP, and isn't anything to do with GrapheneOS.

The GrapheneOS-specific toggle in that menu is '4G only' mode: https://grapheneos.org/usage#lte-only-mode

On GrapheneOS, you're welcome to use whichever best suits your needs.

I don't have a cogwheel next to my carrier setting and so I'm not sure what you're referring to as "4G calling."