Never had a carbon-related failure in any of my issued or personal weapons. It’s a non-starter.
I’ve cleaned the gas tube in my first AR exactly once in 20 years. Zero carbon/gas fouling problems.
Laquered cases getting stuck, and broken ejector claw, yes, but no “s*** where it eats” issues.
But hey, if a Studebaker got Granpa down to the corner and back, then why bother spending money on car with new technology?