You can make up whatever fallacious slippery slope arguments you care to invent, but such routers already exist and they are the best, most secure routers you can buy.
Those routers you can get now are only for dumb residential nonces, and routers for anything heavier duty then that all have at least a console connection available, even if they have a cloud management component.
Name another 7-year-old home wifi access point that still gets manufacturer software updates. The contemporaneous Asus RT-N66U stopped getting new releases years ago and in all likelihood contains a bunch of vestigial vulnerabilities. OnHub got scores of software updates over its life and the only time they had a CVE it was patched and pushed to all hardware globally in less than 24 hours. I don't see how this model of control is not clearly superior.