"Rugged, Reliable Ruger Revolvers!"
Their motto.
Due to the number of potential idiots who max load, or think loading manuals are just guidelines,, I seriously doubt the lawyers would approve. And the engineers who may consider it,, well, they too know how stupid some people can be.
Lastly,, while many of us enjoy a .41 magnum,, Ruger is into SALES. LOTS of sales. Initially, they would sell some. But if they offered it in stainless, many would say; "Not until they make it in blue." Or if offered with a 4" barrel,, many would say; "I want it in a 3" or a 5" or whatever.
Hard to build a model that pleases enough people to where you get a lot of sales!
And as for a 5-shot vs a 6 shot revolver, don't tell the serious custom gun makers who build strong, serious calibers, not to build them in 5 shot.