Until you realize that they're a) very centralized and b) require a lot of empty space in a suitable location that isn't better used for something else and c) consequently cockblocked by various regulations & NIMBYs. Meanwhile we have cities full of rooftops, facades, balconies, parking lots, and much much more other surface areas that are just sitting there without being utilized. It's right there where the energy is also consumed, lowering bills and creating massive interconnected energy storage in the process.