In any case, a catastrophic multi-sat collision would only result in a meteor shower
Previous collisions have resulted in debris that intersected with higher orbits. While those debris themselves will decay, if they collide with something in a higher orbit, a significant portion of the resulting debris will be there for a very long time.
Previous collisions have resulted in debris that intersected with higher orbits. While those debris themselves will decay, if they collide with something in a higher orbit, a significant portion of the resulting debris will be there for a very long time.
Look at the apogees resulting from a major collision in 2009 in fig 3 on page 2