I wonder why solar window shutters aren’t a thing.
Because the source of light is mostly up in the sky, and solar panels work best when they are mostly perpendicular to the direction the light is shining.
Sounds like what you are suggesting is a standalone solar panel mounted on a sun tracking mount above a window? Still, it would be better and cheaper to just lay a solar panel out in the yard and then install a conventional window shutter.
Already addressed.
IMO solution is a ‘european tilt and turn’ window system with an inner window (tint or shade optional) and a solar panel shutter.
With drive motors and suntrackers for the luxury version.
Sounds like what you are suggesting is a standalone solar panel mounted on a sun tracking mount above a window? Still, it would be better and cheaper to just lay a solar panel out in the yard and then install a conventional window shutter.