Elon Musk's most fantastic/unrealistic prediction for Starship cost to orbit is $10/kg. To get to GEO roughly doubles that cost because the cargo Starship needs to rendezvous with a tanker for the fuel to GEO then back home. Intermodal surface freight reaching most of the planet is about $1/kg on the high end.

To even begin to make sense, space freight to would need to be 1/10th of Musk's overly optimistic $10/kg. You could ship the panels air freight and still beat those numbers by a huge margin.

That says nothing of the construction costs. Which for SBS will cost orders of magnitude more than day laborers in t-shirts assembling arrays on the ground.

Every aspect of SBS is ridiculously expensive and requires as-yet entirely undeveloped space-based construction technologies. There's no near-term horizon where it's anywhere close to competitive with ground-based solar. This holds even if you assume over-building surface solar to 3x to match the duty cycle of SBS.