Yep, and it'll likely keep dropping dust for some time to come. Our ROO 23SS had a continual "snowfall" in a couple of the light fixtures and I'd bet the couple who bought it in '13 are still cleaning it out. Rocky was not as much of a dust dropper, but still had some. It's the bumps as you travel that keep those specks moving.
Agree that there is no time in the building process to vacuum up, but absolutely sure I wouldn't want to pay the price for someone to run a vacuum for 2 or 3 hours and get every speck out. Consider it part of the "charm" of an RV.