[simondotau]

The Kessler Syndrome doesn’t apply at Starlink’s altitude.

[buzzwordninja]

My knowledge basically ends at knowing of the concept, so can you elaborate how/why it is different in different orbits?

[kitsunesoba]

The lower the orbit, the more quickly objects de-orbit. This is especially true of the lowest LEO orbits that Starlink sits in, where atmospheric drag also enters the picture. Worst case scenario, a totally dead satellite will deorbit on its own in a couple of years and they can very easily suicide if required to avoid catastrophe.

[throwaway2048]

collisions can easily push things into higher orbits.

[aidenn0]

I'm not a rocket scientist, but this seems unlikely; sure two large satellites colliding could create smaller debris with a much higher apogee, but it seems to me that the perigee would not increase, so it would still spend a significant fraction of its orbit in atmospheric drag.

[throwaway2048]

but could easily collide with something at apogee, especially if the collision lead to a cascading style kessler syndrome event.