"But as you already know, it takes a fair bit of shooting to destroy a good barrel if it is properly cared for. "
I guess it depends on each person's definition of "fair bit".
I get upset if a barrel does not last one season. Over the winter the rifles in use get borescoped so I can plan what to shoot next season, what needs replacing, and what is marginal so I don't go off to an important event with a barrel on its last legs.
I never experienced less than a season od use until I started shooting 22-250 Ackley, loaded with Win760 and the Sierra 80. About 1200 shots, maximum. Since I sometimes shoot 200 rounds in a day, the barrels were lasting as long as gumdrops.
On the other hand, in 1915 my grandfather homesteaded in northern B.C. He brought with him a Winchester M94 rifle in 30-30. That rifle kept the young family in meat (2 moose a year) until 1965. The rifle still has an excellent barrel. It lasted a life time.
I find 308 barrels last about 2500 rounds (blue)and about 5,000 (stainless). These are target barrels used in competition. They group under an inch. When the group opens to an inch or more, they are no good. Since the wear is all throat erosion in the first 2 inches, we cut the chamber off, set the barrel back and use it for another season. The set back barrel is as good as new, except for the shorter sight radius and the loss of 50 fps.
The other calibers I use (6.5-08 Ackley and 6.5-284) both have less life than a 308. They are loaded with 50+ grains of power.