inclusion of more mental health issues in the background check system because there is no (or not enough) causal link? And that we shouldn't take away their gun rights because many of them won't go on to commit violent crimes?

But then you would argue that we should take rights to some guns (assault rifles or whatever you want to include) away from everyone (despite no crime or mental health issue being required), but not the rights to own any type of gun by some individuals because some of them may never commit violence?

I gather this article to some degree, and many that seem to want to dismiss the mental health angle do so perhaps because they want a gun ban, and to them nothing else will do. So they fear this angle may take away from the likelihood of achieving that goal. But you don't strike me as one of those "only one option is acceptable" type ideologues, or even close (even if you would like some type of gun ban), so that's why I ask the questions as the logic is escaping me a bit here.