I think partially but you missed a key factor which is that most new homes in California require rooftop solar. So the net-metering change only affects individuals adding solar since it’s optional for them. SF builds an extremely low number of new homes compared to the rest of the state, so they have less of a foundation to fall back on when individuals stopped installing systems.
Could it be because adoption was already high and ground space is more limited in SF county than any other county in California?
No
“The sudden drop in solar panel applications is in large part due to the enactment of a new rate structure for paying solar customers”
I think partially but you missed a key factor which is that most new homes in California require rooftop solar. So the net-metering change only affects individuals adding solar since it’s optional for them. SF builds an extremely low number of new homes compared to the rest of the state, so they have less of a foundation to fall back on when individuals stopped installing systems.