I agree this is an interesting read although I don't think all nuance is accounted for.
For example, at the risk of being pedantic, what about the case of a peaceful assembly for the purposing of advocating for the right to display firearms? In such an instance, wouldn't the display of firearms be performative speech, as well as civil disobedience?
Further, the author does not take into account all objects which may be used as improvised lethal weapons. Again, at the risk of being pedantic, a hand towel can be used with lethal force by an aggressor with the proper skill.
Finally, I share the author's concerns about the chilling effect. While they don't use this exact phrasing, I think they are speaking to the issue of intent vs. impact, in that not every display of a weapon is intended to intimidate, although that might be the ultimate impact. However, a government edict on display of firearms, where firearm display could constitute speech, would also create a chilling effect, regardless of whether we agree or disagree with the mode or message of the speech.
I would simply amend the essay title to "Guns Are Not Always Speech" or "Guns Are Sometimes Speech."