First of all, gun laws have been more or less the same for the past 100 years in the U.S., so how can they be the cause of the recent rise in mass shootings? Simple answer: they’re not.
So guns changed over the past 100 years, but the laws did not adjust. Sounds like a bad idea. How can a new technology a cause for a new problem? Did that ever happen???/s
Semi-automatic rifles were not overly widespread before the 1990, and when they became, in 1994 there was a time-limited ban for semi-automatic firearms, which then expired in 2004. And what are the major concerns for mass shootings in recent years? It is semi-automatic firearms.
If they were serious about curbing gun violence, their focus wouldn’t be on mass shootings so much as smaller-scale gun crime.
Why do you think they want to ban all guns? But when you've a gun proponents such as in the US you gotta get real about what you can achieve. So it is not hypocrisy to focus on assault weaponry.
That hobby thing can be said about many forbidden things, for example smoking cannabis.
Introducing regulations usually doesn’t mean complete and utter ban.