You’re forgetting “customers see how much prices are up, and just stay home” or “company C, looking to break in, undercuts A and B and changes the market.”
A real UBI is a great fix for capitalism, since it makes “f it, I’ll just stay at home” possible.
So, EVERY radio on the planet is suddenly overwhelmed by broad-spectrum jamming from orbital sources? Every cell phone, wifi, broadcast TV, satellite, AM/FM?
A bunch of people die,.due to distracted-driving car accidents with no way to call for help. News and government adapt modestly quickly, since the Internet itself runs mostly on already-shielded wires. There is a run on ethernet cables and phone modems for a bit, though, since not everyone has one. Navigation and timekeeping get harder, since no GPS or radio time sync, but humans adapt to those fairly quickly.
Long-term consequences depend on how long the aliens keep it up. It’s definitely a holy crap there are aliens! moment, though, since a bunch of sudden radio transmitters would be detected in the sky and identified as alien tech way before the toilet paper shortage even starts.