Something with a higher bar of quality than the typical consumer electronics you pick up in the bargain bin at Newegg/Amazon/Wal-Mart.
I think it's within the realm of possibility for consumers to install routers/gateways that are competently engineered. It's flat out impossible to ensure every IOT device a consumer owns has even the most basic security principles covered.
If a home has a desktop or media PC, it could potentially run a router/gateway VM on platforms like Qubes, Genode, etc. The router VM would be isolated from desktop/media VMs, and would have the benefit of running a BSD/Linux x86 OS that has automated updates. New wifi standards can be supported by upgrading a USB or PCI WiFi adapter, rather than buying a new router.
I think it's within the realm of possibility for consumers to install routers/gateways that are competently engineered. It's flat out impossible to ensure every IOT device a consumer owns has even the most basic security principles covered.