In my specific case, I barely use much power so home solar covers basically all of the usage, my bill is dominated by the daily charge, so the usage component is practically irrelevant to me.
Yes, grid scale deployments are cheaper, but I'm generally guessing a lot of the grid scale solar deployments do not price in the grid infrastructure adaptation costs, and I'm not even talking about grid storage.
Consumer rooftop solar is fundamentally democratic: it reduces reliance on centralized institutions for power delivery, Make society a lot more resilient in bad weather and other emergency situations, insulates everyday people from wild variations and petroleum and other consumable energy availability.
Combined with plug-in hybrid electric vehicles, it would enable electrification of 80 and 90% of daily driving without grid infrastructure costs.
Here in Sweden nearly all of the electricity bill you pay is concentrated on the winter months when there is literally zero sunshine. Even then solar is popular here. I calculated that installing solar would take around 10 years or more to pay for itself, but I have very little hope to stay in the same house all that time so for me it seemed like a bad investment.
That said, if you live in places where it’s sunny most of the time even in winter, like Australia, then solar is absolutely great, just don’t assume most places are like that.