The problem that this is trying to solve (Isolation) seem possible to solve once you get away from a mismanaged wifi setup.<p>Too many devices supported by one router. This can be solved with more chipsets per router, each with a slightly more directional antenna (as opposed to dipoles being standard).<p>Turning down transmitter power on routers, if you want fewer devices (such as one 20x20 area instead of pi(150)^2 ft) you can turn down the tx power. Moreover, using 5ghz already starts limiting wall penetration more.