No. I think it depends how you define collectors and also how ancient you are. Certainly no import markings is preferred to a gun with import markings. But we don't intentionally damage an all matching by shooting it just because it arrived in the US after the gun laws changed. Consider Eva Braun's PPK which is believed to be the pistol used by A. Hitler for his own suicide. After the fall of Berlin it fell into Soviet hands (last seen in the Soviet video of Hitler's autopsy) and is presumably in some dusty NKVD/KGB/FSB box in an old Moscow warehouse. Should it be offered for sale to Century Arms, and sold on Classic Firearms, would you refuse to consider it because Century put import stamps on it when bringing it into the US? Fire damaged of course it isn't a shooter anyway, but you get the idea I am sure. Import marks have to be considered in terms of what would otherwise make it a collectable.
If G. Lugers own Baby Luger was re-blued by its current owner or even chrome plated, would you have no interest because of that? Would you decide it is okay to shoot it because it had been re-blued, even though many of the parts are custom parts and you will probably never find a match on Ebay?
Refinished guns fall into two classes. Professionally redone, and amateur jobs. Re-blued by the Wehrmacht itself is also quite acceptable to most collectors. We agree an all matching re-blued or nickeled by someone using a belt sander and a jar of Numrich 44-40 cold blue is worth much less than one not suffering such treatment. Then again the belt sanding probably removed some of the serial number stamps anyway, so it's still being an all matching becomes dubious.
If someone took an all matching and stored it in a damp holster so after a decade or three it was coated with pitting and rust and then it went to one of the four or five professional restoration guys for TIGing up the pits and fully recreating the original blue and straw, would I consider that gun a shooter? No. If I got it at a shooter price I would be overjoyed, but I wouldn't treat it a shooter. Likewise I would expect it to cost more than a true shooter (mismatched with nickel flaking off, etc.)
