I think these are good points and really all of your points that I have seen are pretty reasonable ones.
The main issue is that at this point owning a gun has become part of identity politics in the US. The whole culture around is a defining feature of a fair number of people and others do not want to see that messed with to varying degrees.
As soon as something falls in that range it becomes a controversial and hot button issue. It is the way things work in the US.
And often what happens is governments tend to cave to the most unlikely but vocal (and likely to vote) actors. Does not matter if something is in the public interest or any interest other than some thoughts.
Keep in mind, the US public in general, at least based on polling, has some strange ideas on things. And most of it is very much associated with ideology and identity. Not unique to the US but some of the issues we have chosen to make that way are odd in the world scale.
I will say, I have been disturbed by how much conspiracy theories based on anything are just believed without information. And many will believe it even when all evidence supports that the thing did not happen that way at all. It is scary.
It is pretty much what the death of reason looks like.
What conspiracy theories are you talking about? I certainly don't believe in any, outside of JFK's death and assassination.
The point about guns though, is that they are often used in self-defense (More than even Obama thought.) and that criminals are often deterred by them, so you can't just exclude people from buying them just because other people misuse them (Just like you can't stop one person from buying alcohol because there are people out there who drink and drive, etc.). Again, MOST guns that are used in crimes are NOT obtained legally!