SpaceX also intends to debilitate two of the satellites that work to test the process.
It's still early for Starlink, but it suggests you will not see a multitude of dead satellites that would submerge Earth's orbit. Concern is more scales. Finally, SpaceX hopes to put the constellation of almost 12,000 Internet satellites into orbit. There is no guarantee that SpaceX will enjoy similar or better successes for all of them. The comparative speed of failure would still affect hundreds of satellites over time, thus increasing the risk of the existence of space remains.
Fortunately, satellites will not last forever. SpaceX already expects satellites to last five years before entering the atmosphere. It is only a matter of how many of these machines are controlled by a fall, not in unpredictable ways.