It isn't an opinion. It's a fact, as evidenced by the statistics cited in this thread.
A statistical fact tells you about a number of samples. It does not tell you a "fact" about the specific case.
The statistics tell you that in a population possessing guns those that have them in the house are in the sub-population that will have more gun incidents than the sub population that doesn't.
It doesn't tell you a fact about one individual.
My mother and I used to endlessly argue about smoking. I couldn't say that she would for sure get lung cancer (it killed her in the end but at 89) all I could say was there were two large groups of people out there and one had many fewer deaths from various cancers. I couldn't say for a fact that going over to join one would mean I wouldn't get cancer but I could say it seemed like a reasonably bet to join the that seemed to be doing better.
You can't tell ICANT that he is less safe with a gun in the house as a fact for him based on population statistics.
But what he should ask himself is, having chosen to join a population that is demonstratively less safe, why should he think he isn't subject to whatever causes them to be less safe.
The fact is he has chosen to put himself and his family and friends into a factually less safe group of people without knowing if he is someone different from that population so that the statistics of the population don't apply.
So your argument isn't that guns aren't responsible but that there's no practical solution.
I'm across the 49th up north where we have pretty strict gun laws and, as you've noted, a lot less killing and, I think, suicide. But maybe Hyro has a point: How do you get from where the US is with people like Hyro and ICANT in it to where we are in Canada. Your political system is on the edge of breakdown so how do you do what Australia did with the gun numbers Hyro points out, the power of the NRA, and people like Hyro running around?
I'd like to see you fix it all but I honestly don't know how you get there.
Our problem is they won't. The US represents a significant long term risk to us. I think there is squat we can do about it and when things get bad any neighbor would be dangerous.
Since we are not going to take the action (see Green New Deal) required over the next decades I'll have to take my own action to avoid the consequences. I'm 73 plan B is to be dead. But I have kids and assholes like the republicans (and our conservatives) are going to risk their lives.