Laser links work. IIRC Google even tested a laser link between balloons in the atmosphere. While most of the more-advanced uses I have seen in the news are spac

Laser links work. IIRC Google even tested a laser link between balloons in the atmosphere. While most of the more-advanced uses I have seen in the news are space-to-ground links, there is nothing, in principle, that would prevent satellites in a LEO constellation from using laser links. The questions is more about how well it works in practice. In 5G, for example, beamforming mmwave links work great when you provision it for fixed-wireless access (FWA). FWA is really real. But 5G beam "sweeping" and beam steering to track multiple moving devices are much, much harder to make work in real world situations. It all works in principle. But FWA is a real reliable product today. 5G "beam management" is still almost entirely a demo or in the lab.