Suburban homes capable of overproducing power also have by far the highest per user grid maintenance costs due to simple distance. I agree you would see an uptick in solar adoption with your scheme, but only because apartment-dwellers are being conscripted to subsidize your grid connection.

Early subsidy plans were short sighted and came from politicians, not grid operators, and gave homeowners a massively inflated sense of the usefulness of the meager kWh they produce. Power is cheap, infrastructure is not. It's far better deal for the commons if you use all the kWh you produce (via storage) and pay what it costs to deliver a grid connection when you fall short.