I don't think that over 20,000 laws restricting firearms can be called doing nothing, but they have been ineffective.
What has been shown over and over is that all these laws, including the basic laws against murder and assault, have not stopped criminals or people determine to do violence.
You see the fallacy with gun laws is that bad people don't abide by them. All gun laws do is restrict the constitutional rights of the law-abiding citizen.
For some people, mostly on the left, they feel passing one more law will fix anything. Most gun laws are feel-good laws, not do good laws. Passing a law because it makes you feel like you're doing something, even when it doesn't address the real problem, is just dumb.
What needs to happen is we need to look at the cause of the violence and have discussions on how to address that. Firearms do not cause violence, they are just a tool. Like any tool, they can be misused, like cars, explosives, knives, baseball bats, etc. The problem is more complex than that. We don't laws restricting firearms, we need to look at mental health issues, bullying, poverty, and a host of other issues if we truly want to do good and reduce violence.
With over 300 million firearms and over 1 trillion rounds of ammunition in the hands of private citizens, if firearms themselves were the problem we would all be dead.