So if they all burned up today it would be around a 6% yearly increase, globally? (1663 / 5200 * 5). And that's probably the most forgiving estimate I could come up with, I think your ~20% number is more accurate for future projection purposes given most of the mass was launched in a much shorter timespan.

Then the real question is what effect does space dust have on the earth's atmosphere (if any).

[1] https://en.wikipedia.org/w/index.php?title=List_of_Starlink_...

This is basically the reality of government leaders jetting in to global climate change conferences.

Lots of people incorrectly think that the upper atmosphere is pristine and you would never normally get metal up there. In fact thousands of tons of micrometeorites hit the earth each year, depositing lots of rock and metal up there.

This means that the burning satellites cause an increase in metals deposited in the upper atmosphere. We’re not going from nothing to many tones. We’re going from many tones to slightly more tones.

There is an open question if the increase is a problem, but it’s less likely to be a problem than if we were going from nothing to something.