A lot, mostly NDs. I can't find any statistics because google sucks these days, but you can find video after video after video of people shooting themselves and their friends with "empty" guns. I used to frequent the /r/IdiotsWithGuns subreddit. Some great examples of how badly someone can ruin a life in an instant on there

I think most gun deaths tend to be handguns, and tend to be suicides, which would probably be people who would still be allowed to have a firearm in this circumstance, though I can see the insurance dissuading that in the case of people who are killing themselves on impulse (though I would think a wait period would be equally as effective, is already implemented in some places, doesn't financially discriminate, and neither legislation nor really any legislation we have actually would flag someone as being at risk if they wanted to kill themselves, except for the kind of pathetic mental health check form).

The other large category of gun deaths tend to be what is defined as "organized crime", which tends to stem from a couple different convergent factors. High value property, in drugs, that exists outside the legal system but still must be protected, lack of real social safety nets, large amounts of poverty, redlining, etc. . Generally though these people aren't like, legally acquiring their firearms anyways. What they are doing, and what is a real concern, is them acquiring firearms from legal gun owners, as the US has quite a lot of guns and not a lot of limitations or protection on them. The cartels can get a bunch of fourth generation military surplus used up garbage at an expensive black market price, or they can just rob like one gun nut, shave off a sear, and bing bang boom you have a spiffy new gun, pretty easily. I don't have a great solution to that problem, but in any case you could tackle that issue from the other side by just providing social safety nets, legalizing drugs, trying to lower housing prices, shit like that.

The stand out category in everyone's mind tends to be "mass shootings", or, lone wolf, usually stochastic, terrorism, which is kind of an interesting hot button political issue. By any analysis, though, it tends not to be a huge issue in terms of raw deaths, though, I would like to see some sort of crackdown on it happen, but you would probably need some even-handed, discriminating approach to that, or, again, better flags for mental illness, rather than a large encompassing law. Also getting a shoutout is unjustifiable police shootings but I also don't have a great solution beyond that outside of abolishing police, and getting rid of this stupid fucking patent that axon has on the taser.

In any case basically, you are correct, this law's gonna do jack shit.