How many ships are arctic waters? Almost none. I bet 99.999% of all shipping is in mid-latitudes.

And as said, the bandwidth will drop when more people sign up. Imagine you live 100 km away from a city (like Toronto, Vancouver, Denver or similar) in a small rural town. You will have to share the same satellites with million of Tesla fanboys from the next big city. It will be a blessing in really remote areas, hours away from civilization, but otherwise ...