I dunno, but that doesn't look "minor" It's kinda deep. I would consider a shallow crease minor like when a tube hits a sharp corner, and the paint does not chip off, but that almost looks like someone shot the tube with a bullet. Do you know what caused it? The frame is a good candidate for a full frame repaint and repair of the dent as much as it can be repaired. I suspect most restorers will try to flatten out most of the dent with straightening blocks but finish it off with some filler.
Unfortunately, Collectors of high line Italian classic bikes tend to be perfectionists and will ask for quite a bit from the price a perfect one would have sold if they see that much of a dent. I would say 20% off from the frameset as-is at a minimum would not be surprising. You can have the frame restored/repainted and maybe recover some of that money. You might also consider parting the bike out if you want to make the most money out of it, but that would be a shame as the components and frame seems to be original to each other. I vote for a full resto....but then you might not want to sell it once it's done!.........and we would certainly understand!.....

Chombi