Not the person you're replying to, but I fully support repealing the 2nd amendment and strictly regulating gun ownership, up to and including total bans on certain classes of firearms, magazines, and ammunition. I would also personally have no problem with a total ban on any kind of firearm ownership, but I don't think the evidence supports that a total ban would make us meaningfully safer than more targeted restrictions and regulations. But for the guns we might allow in my fantasy of a US with sane gun laws, every gun owner should be required to take both a safety course and general training course, and complete a practical skills exam before being licensed (yes, licensed) to own a firearm. That training should have to be repeated (perhaps an abbreviated version) at some reasonable interval, such as every year or two.
Regarding your nitpicking of what "assault" means, that's irrelevant. But to discuss it anyway: "assault weapon" has not become an umbrella for any semi-auto weapon. Semi-auto pistols, for example, are not what people are talking about when they want "assault" weapons banned. For people who don't really know much about guns, "assault weapon" means "a type of gun that someone in the military on a TV show or movie might have slung across their chest". An imprecise definition, to be sure, but in general I'd agree that no random civilian has any need for such a weapon. And any civilian who believes they have an actual need for such a weapon probably should not be trusted with one.
I do know people who own some of these types of guns. They're responsible, train, and treat the weapons with the respect and care they are due. But I still don't think they should have them.