I'd have to say its not that shooters don't know whats going on inside thier barrel but more they don't know they should know

Therefor they pay little attention.
Borescopes might be nice but not entirely required.
My comp guns run all season without cleaning.
Its about choosing the correct powder to allow that to happen.
In the PPC for instance N-133, h-322 XBR are no shows.
They shoot best with clean bores
Ramshot X-terminator and HBN coated pills is the ticket. 5,6, 700 rds without loosing accuracy.
Same goes for the 6BR with 68gn pills.
One of the fun shoots I attend may require 100 rds down the barrel with little time for swabbing.
To win in such an environment one needs to learn some lessons or just get lucky. Just lucky is rare.
I know exactly whats going on inside my barrels without a borescope.
Simply because early on I discovered whats happening in the fouling department has absolutely Everything to do with accuracy or lack thereof and paid strict attention to what the bore was telling me.
Its a subject rarely discussed on internet forums which to me implies not many are paying attention.