I'm curious about the feasibility of modulating light onto a solar panel. I feel it would not be feasible, except possibly onto a single panel at a time over a long time period. Just a gut feeling based off radio stuff (GPS).
Nothing prevents the satellite to transmit the commands at night, if that feels more convincing to you.
Ask yourself what is the active area of a photodiode in your TV/... ? What is the active area of your light-bucket on a roof?
If we are discussing the solar panel that powers your outdoor garden light, I don't suggest to apply the precautionary principle, but we are talking about products that sum up to a significant fraction of grid power generation.