I'm not saying it isn't a problem, but aside for Covid there are usually 10,000 flights in the air at any given time on average, with several hundred thousand flights in 24hrs. A lot of those are concentrated during the day over the continental US, which is the most congested region in the world. So on that basis, an evenly distributed web of LEO satellites should be manageable, especially as they will also be much more vertically distributed than planes.