Count in oversubscription rates for residential, and consider that most people, despite what they say or think, will end up on 2.4GHz wireless in the home due to 5GHz sucking more than a room away - that ends up being a very scalable solution for residential service.
Um… 5GHz works a lot better from one end of my house to the other than 2.4Ghz due (in large part) to this fact… Almost every one of my neighbors is using various 2.4GHz devices including about 45 external SSIDs visible from the center of my house using the on-board antenna of an ESP8266 board from Adafruit. The noise floor and congestion on 2.4GHz in many urban settings, especially here in Silicon Valley makes 5Ghz a much better option in any home where people are smart enough to pay attention to the difference. OTOH, since the WiFi consortium took away the ability for consumers to easily differentiate (it’s all “n” or “ac” now regardless of frequency) and you have to really read the fine print on the side of the box to find a 5Ghz capable WAP at your local big box store, most consumers end up on 2.4Ghz because those are the least expensive routers on the shelf. Personally, I don’t mind this, but I think the 2.4Ghz prevalence has more to do with consumers not knowing what they are buying than it does with performance. Owen