Love when a Lazarus post rises from the past,

Obsolete may be too subjective a term, unpopular yes.

41 had good numbers on paper but its name alone relegated it to live in the shadow of the .44 Magnum which sounds more powerful and has a baby brother that is easier to shoot at paper targets aka .44 Special.
The timing of .41 was not ideal either as many of my older shooting friends related to me that they wanted Dirty Harry's gun when the film came out, when offered a .41 instead they said no I want the .44 , after all Harry Calahan said it was "The most powerful handgun in the world and could take a man's head clean off".

I liked the idea that .41 should have been a .40 Magnum ..
I guess they kinda did make it a few years later but they called it 10mm and its rimless to go in the more popular autoloader.
On paper my .357 is close enough to 10mm so I'm good there,
the idea of .40 SW revolver does sound fun, so does a K frame 9mm .