That is technically true for this batch of satellites. However at the next shell out that they're planning on using (1150km) it can take a really long time for an orbit to decay (decades or centuries depending on the size of the thing). There's still radioactive crap in orbit from Soviet satellites that were orbiting at 900km more than 40 years ago.

All of these automatically fly themselves to destruction. So we are really only talking about a few defect ones.

Once we are launch 1000s of satellites we are defiantly going to have servicing satellites out there. Refueling, orbital maneuvers and so on.

Even in the worst case, decades is still not that crazy. The locations are known and can be avoid.

This is a problem, but really not any kind of gigantic issue that should stop progress.

and they will be replaced after that