The single largest hurdle to this technology has been high launch costs. Microwave emitters, waveguides, high-efficiency rectennas, and all the other stuff has been old-school since the 1970s -- and we have learned a pretty good chunk about 'assemble stuff in space', too.
Once again, it is SpaceX to the rescue. Our human settlement of (& enterprise in) cis-lunar space is all fundamentally bottlenecked by launch costs, which SpaceX has been relentlessly driving down. When Starship becomes available for transporting cargoes -- probably sometime in 2023 -- launch costs will begin to drop even further. With Cheap Access To Space (CATS) expect to see a large jump in universities and businesses trying all sorts of new things -- including space-based solar power.