China has successfully transmitted data at 1 gigabit per second (Gbps) from a geostationary orbit using a 2-watt laser
Speed of light and all that. I know someone who uses a VoIP softphone over a traditional, geostationary satellite, internet connection. It's awful. The round trip time is so long you practically have to say "over" and "over and out" to control the conversation flow.
The key thing about starlink isn't just the bandwidth. It's the latency, because the satellites aren't that far away.