you can argue about gun laws all you want but it wont change the fact that they will always be easy to obtain illegally, as sad as that may seem it is 100% true. no it's not too late to have stricter laws as to acquiring firearms. but they're mass produced across the globe every single day, they will always be in circulation. they have been for a very long time now. if someone really wants to get one, they will find a way. some people just want attention, they want to be remembered for something devastating, some people just snap and thats it. maybe he had a terrible upbringing or came from a broken home, you can argue mental issues all you want as well.
tragedies such as this will never stop, poverty, struggle, bad areas, shitty parents, gun control, drugs, you can argue any of these issues as far as what may cause people to commit these acts but it doesn't mean its going to stop.