No, obsolescence by definition is something that has been replaced or fallen out of use, .41 Magnum hasn't been replaced, nor has it fallen out of use.
Nothing has ever been proposed as a replacement for .41 Magnum, the cartridge is still in production, and so is the Smith & Wesson Model.57.

So no, it's not obsolete, not by a long shot. Not 11 years ago, not today either.

An obsolete cartridge would be something like Volcanic Rocket Balls, neither Volcanic Pistols, nor Rocket Balls are in production, and they've both been replaced. Rocket Balls were replaced by Metalic Cartridges, the Volcanic Pistol was replaced by Revolvers.

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Shooting Comfort is bilateral.