Core Telephony Constants has shown up and provides 2 new strings, CTRadioAccessTechnologyNR and CTRadioAccessTechnologyNRNSA, both available from iOS 14+ (reasonable given iPhone 12s are first with the tech). This should be reinforced by the term NR, which seems to be part of 5Gs naming 5G NR (New Radio).
CTTelephonyNetworkInfo().serviceCurrentRadioAccessTechnology.
