Registration won't prevent mass shootings. Neither will banning bump stocks.
Nothing being suggested here is going to address mass shootings or gun violence. This is a fact. You can implement whatever reasonable restrictions you want, tomorrow, and you will still have regular mass shootings all over America. The gun murder rate will also be unaffected. The article above is correct in that regards.
The reason for this is gun culture, not guns. There are plenty of Western nations with ready access to firearms, of all types. None of them experience mass shootings or murder anywhere close to what the US does, whether you are talking about per capita or just in absolute numbers.
The fundamental, unique difference is that America believes people have the right to a firearm, and have built a culture around it. The idea of concealed carry being permissible and actually a positive impact on society exists solely in America. The idea that you can protect yourself from overbearing government by owning a firearm exists solely in America (I'm speaking in terms of Western nations here - there are plenty of third-world shitholes where this belief is both reasonable and widespread). The idea that firearms are just "another tool" exists solely in America. The idea that having a firearm on your person or in your home makes you safer exists solely in America. All of these beliefs sit at the core of gun culture, which is the single greatest roadblock to sensible gun regulation. Make no mistake, this is your fault. No, not the massacres and murders themselves, but the inability of the American government to arrive at a compromise.
This is why it is important that Americans, and leftists, reject any further calls for compromise. Because that isn't what is really being called for. What you are actually calling for is the maintenance of the status quo, and no real action on gun violence whatsoever. Your ilk must be utterly broken and subdued, and only then can we talk about "compromise."