You are right and this is a good point BUT the overall rate of murder has risen. So if the point is to actually save lives then the laws were not effective. If the point was to stop mass shootings without regard for how many lives are actually saved - then yes, it has worked.

Of course, there are other ways to mass kill people. Governments drop bombs, for example, which I think is evil. I am an American but I am ashamed that my country dropped bombs over Nagasaki and Hiroshima, particulary because, if you read the history - we didn't have to do that to win. We just had to give the Japanese a little bit of dignity.

Other ways that people have managed mass killings without guns in recent years - using a car to mow down people, using a pressure cooker (Boston bomber), using arson...