Most astronomy is done with computers. It should be easy for a computer to ignore or subtract all known satellites. If you only get 900 exposures of some new comet instead of 1000, that's still plenty. And we'd need many orders of magnitude more satellites to make 10% of astronomical photos unusable.

I hear the astronomy argument all the time, but I just don't believe it. If satellites are ever cheap and plentiful enough to make that kind of difference, the astronomers can launch a thousand Hubble-style space telescopes and timeshare on those.