Yes, of course, gun legislation needs to be more restrictive. IMO all nations should ban all guns for civilian use, including sport.
But there is a bigger problem.
Anti-democracy forces are on the rise in this world, again. Racism, bigotry, discrimination against all manner of "them" expressed in ways from subtle to openly violent are finding receptive supporting populations throughout what we used to consider the strong stable democracies around the world.
Global economic disruptions due to sever climate change will only get worse from here. The rise of the violent right will continue to grow. Our grandchildren will suffer like no other generations before.
The last time the world had to fight off this kind of fascism it cost us more than 80 million dead and, in today's money, $15 trillion. I fear this time the effort won't be so cheap or limited ... or successful.