Scientifically, yes. But legally, governments control who can broadcast over which frequencies. The FCC has jurisdiction in the US for transmissions between 8.3kHz and 275 GHz., because those are most useful for communication.

Visible light is a much higher frequency. And when you think about it, it would be bonkers for a government to regulate visible light as if it were a radio emission, because the Sun already emits a ton of it. I'd like to see some government try to license Sunlight....