Just adding onto your comment, Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap. 2. The wifi chipsets they us

Just adding onto your comment, Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap. 2. The wifi chipsets they use are basically their own self-contained computers that can manage scanning at low-power without taxing the CPU. 3. At least for new HW, some of the 5G-NR stuff really isn't well optimized yet, not as bad as LTE originally was... but it's entirely possible the new modems for now are a little power hungry. Turning on wifi makes the cell chipset track less carriers, typically it'll just hug to one low-band carrier for status/push messages instead of as many as 5 or 6 carriers. EDIT: Phones usually only transmit on one channel while receiving anywhere from 1-7 different channels at once, only the recent flagships transmit on 2 or 3 right now.