CZ 75B for range & comp. games with light loads: probably around 40K rds, but I've quit tracking it.
With this all steel pistol and light load, the barrel/chamber, slide etc don't take a beating; so I don't consider it a high round count at all. I wouldn't be surprised to get 100K or maybe a lot more out of it.
On the other hand, If I were "buying" this pistol at a pawn shop, I'd look it over and say: "Man, this is sure no safe-queen". External (tilt-) barrel 'polishing' marks, holster wear marks, etc. all point to heavy use.
My High Standard .22, probably has 5 times this many rounds through it, and I don't consider it a high round count. It looks and shoots like the day I bought it in 197(?).
I didn't vote: With cars, I consider 100K miles "a high round count" and look around for a replacement.
The type of pistol (or rifle), caliber and load, varies my definition of "high round count". Why? Round count doesn't really matter in some firearms. Shotguns, some wheel guns, .22s all come to mind.