Please consider that the item in question wasn’t the issue, it was executive action which made people overnight felons that is. If if bumpstocks are okay, then what is your limiting principle?
If fully automatic weapons are against the law, then it is not a stretch to include bumpstocks. Not that I agree with banning fully automatic weapons. But still there seems to be good reasons to ban RPGs, no? So now it’s a matter of where you draw that line. Red flag laws have no line, they are all or nothing.