He sold off his .22 because he WANTED to do so. No explanation needed - his gun/ his choice.
He asked for opinions............
And as such, sellin a gun because he shoots it too much is backwards. It's like devorcing a hot woman with a great personality for an ugly woman who whines too much. It's just wrong.
You, the OP, are worried about SD, I get it. But there are about a hundred other aspects to guns that you are missin. Almost feel sorry for ya.