[pepesza]

Think of Kessler syndrome. One can imagine that blowing (small) N of them would create a cloud of shrapnel posing danger for the whole network. Birds are on really low orbits, so it would clear after some time, but network might not survive this.

[ric2b]

Starlink satellites are in decaying orbits, eventually they fall through the atmosphere and burn away.

They have some propellant to make adjustments and stay in orbit a bit longer but if you blow them up you just make the decay process quicker.