An intriguing analysis of supply and demand.
In short, the increase in solar generating capacity has caused peak electricity demand to occur in the evening as solar generation tapers off, as opposed to mid-afternoon in years when solar's share was lower.
Therefore, the rates of small-scale, residential generators 'selling back' solar power to the grid have gone down, upsetting residents who invested significantly in solar generation, and assuming their ROI would be based on unchanged supply-and-demand characteristics.