Those round counts are probably low as I destroy range records after I sell a gun. (I keep track of every round fired from every gun I own).

I say this, because I know I fired 1500rds through one particular 9mm over the course of 3 days.

Now that I think about all of the guns I sold in 2019 ... I bet some of those round counts are half of the actual. I bought 20k of 223 Rem and don't have a single case left.