The .357 mag is the second most popular revolver cartridge in sales behind the first place revolver cartridge, being the 38 Special. Both, individually outsell every other revolver cartridge manufactured and sold. And as far as manufacture of revolvers, the 357 mag revolvers way outpace all other chamberings of revolvers made, to include 38s. So, add 38 Special ammo sales with 357 mag sales, and they add up to a pretty big chunk of both ammo and weapon sales.
So, not sure your point. If you think somehow the .357 is dead in the water, then what do you think of .45s, .44s, and .41s? None of those come close to being as popular in sales and profits compared to the 357. None of those come close to the total number of 357s built and sold each year. I just do not see any of those revolver chamberings going by the wayside, and I certainly do not see the most popular revolver made, probably going back decades into the last century, as being anywhere close to dying out. The gun and ammo makers just plain see too big a chunk of their profit out of the 357 to let it go.
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