Earlier quoted context omitted.
Space is hugely, vastly, mind-bogglingly big. Useful low orbital shells around the Earth are an awful lot smaller. They're still big, like the sky is big, but airplanes do manage to, at least somewhat regularly, collide with each other "in the middle of nowhere" (most midairs are around airports, since there are a lot of airplanes heading in and out of them). Aircraft debris, however, falls out of the sky in short or…
Yes, space is big. Lower earth orbit is still very big. However if you have dozens of operators, each with thousands of satiates making multiple round the world trips. The chances of a specific satellite colliding perhaps is tiny (given how big space is). However the chances of one of the thousands colliding with any of the other thousands over any of their orbital periods increases exponentially as the number of sat…
> There are currently over 1,600 Starlink satellites in orbit, and that number will continue to grow; SpaceX has filed paperwork for up to 42,000 satellites for the constellation.
https://www.space.com/spacex-starlink-internet-satellites-la...
They're aware of the risk of collisions, but toss in a few more vendors trying for the same size, and you can have potentially hundreds of thousands of satellites in the shells. They're big, but they're not that big.