How the fuck is that the best option right now? Why can’t my provider make use of economies of scale and buy a container ship full of solar panels.

Same reason why the cheapest option for a household that already owns a gasoline powered vehicle is to keep using the vehicle they already own.

If it were starting from scratch, solar+battery would be cheaper than new gas. But as it stands now, the gas plant is already built and operational, so a new solar plant would have to compete with “already built, no additional funds necessary for construction.”