> 5G (at least the high speed kind) has really really bad penetration,

To be fair, both Fiber and Coax have far worse "penetration"; Changing the definition of a 5g fiber connector from "wireless to devices inside of a home" to "a small antenna you put on the outside of the house or by the window and a wifi router inside" drastically changes the definition, keeps infrastructure cheap, and the cost at the home is still significantly less.