It's driven by lawyers and law suits. They've got to be able to prove they tried to fix the problem. Then when someone shoots off some part of their anatomy with one, they won't get sued.
I haven sent any of my old three screw Ruger's in. I and my kids know to carry them with the hammer down on an empty chamber. I'll let the kids worry about what to do after I'm gone. They can keep them, sell them, or send them in for the mod if they want to.
I like the trigger pull and cylinder indexing too much to mod it. Fantastically accurate revolvers.