Re: Random
Probably because it wouldn't help much. These devices don't process speech locally, so if the connection goes down, you couldn't tell it to turn on the radio. You could put a normal set of radio controls on top, but now that's a larger change that the manufacturer doesn't care about.
I don't understand your hotspot suggestion. Are you suggesting that the voice assistant should have a WiFi network for radios? Why? And if you're instead suggesting that it broadcast radio signals for a broadcast receiver to pick up, that's illegal. I'm not sure what you want.