The part of 5G that gets thrown around a lot with high speed and capacity is mostly based on mmWave bands(think 10's of Ghz) which attenuate incredibly quick. Most of them are nearly direct line of sight. You already see some issue with 5Ghz wifi not going well through walls, there's a high chance you'd be falling back to one of the lower speed bands inside.
The other thing is there's a non-zero amount overlap in the way spectrum is used in wifi and 3/4/5G, MIMO, spread spectrum and other approaches are all trying to get as close to the theoretical limit of the channel bandwidth. When you start looking at large scale wifi deployments it starts getting split into cells of channels not to dissimilar to cellular deployments. There are some differences and certain bands benefit from discrete allocation/cell management but at the end of the day it's all radio waves over the air.
This would seem like an argument for installing wired / wire->mesh 5G base stations around our houses instead of the wifi repeaters we currently use..
Amazon in the past flirted with the idea of building a mesh network of Amazon IOT devices so that your neighbours Echo could connect yours to the internet even if you didn't have a connection. BT in the UK offered reduced price broadband if other BT customers could use a WiFi Guest network from your connection - so BT customers had like 90% free wifi coverage in cities.
I can see a amazon deploying Amazon Echos and automation poducts as 5G enabled IOT devices that backhaul to your home internet but also mesh with neighbours, then eventually deploying its own outdoor 5G coverage and suddenly becoming a mobile network.
Yes it's possible but AWS focus is to be the Layer 1. They're doing it for data and can easily replicate it for voice if there is a use case but at that time they're directly competing with Telco, a fight that they may not pickup at this time. Ideally they would utilize all the unused bandwidth & reuse it. So one neighbour can provide internet + mobile to entire street
The other thing is there's a non-zero amount overlap in the way spectrum is used in wifi and 3/4/5G, MIMO, spread spectrum and other approaches are all trying to get as close to the theoretical limit of the channel bandwidth. When you start looking at large scale wifi deployments it starts getting split into cells of channels not to dissimilar to cellular deployments. There are some differences and certain bands benefit from discrete allocation/cell management but at the end of the day it's all radio waves over the air.