In looking at my log very quickly, I picked seven different handguns that each have a round count that has been specifically logged over 2,000 rounds. A couple of those seven are over 4,000 rounds.
I can tell you that if I put each of those six guns in your hands, only -ONE- of them would look, in any way, like it's seen a lot of use. That one is a GSG 1911-22. It is a
low cost handgun and it really looks like the manufacturer put all their effort in to the quality of it's functionality and ZERO effort in to the durability of it's finish. It kind of looks like total hell, actually
But it does have over 4,800 rounds with near flawless performance.
To be fair, one of the others looks a wee bit "less" than new, and that's a circa-1994 Taurus PT-99AF. It's got 2,837 rounds through it, and still runs great.
Even still, your original question is quite compelling. My handguns that do ring up a decent round count usually do so about 100-300 rounds at a time, then they get cleaned. If we're talking about a gun that was in very specific use in competition, I think we'd see FAR more visual clues that it's had an active life, and it would really have a higher, maybe even eye-popping
round count.