And I know at my house I have a master cut off switch.

For obvious reasons, we need it to not backpower the grid during an outage. In theory, we could have the owner shut off their main breaker, then override the inverters lock-out. However, any inverter that allows that cannot be allowed on the market, because someone is going to flip the switch on the inverter without flipping the main breaker.

We would need the switch on the breaker to communicate over to the inverter to allow for safe operations in an outage. We could probably do that communication over the existing power lines, but you would still need an electrician to modify the fuse box to do so; which defeats half the point of plug-and-play solar.