> Why shouldn't that be true practically every consumer home in the world?

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.