Rooftop solar costs 3x more per watt than utility scale. The only reason it would pay off is that you're able to avoid grid maintenance costs built into per-kwh pricing.

Residential electricity pricing is 3x-4x wholesale pricing.

Which is gaming a particular kind of rate structure. They would not do nearly as well if grid maintenance charges were decoupled from consumption.

Rooftop solar (ideally with battery backup) allows you to be independent of the grid (yes, even if you're interconnected, if you do it properly), which means PG&E's garbage infrastructure can largely become irrelevant if your system is properly sized.