Inshala, I don’t disagree with most of your post.

We do get too wrapped up in our favorites and personal choices.
Sometimes there’s reasons for the choices though.

Me, I can’t shoot Sig handguns for beans. The grip while it feels great in the hand and the guns are wonders of mechanical engineering, there is an issue. There is a projection on the left side of the grip frame that strikes the joint of my thumb in firing, my thumb goes numb within a couple of rounds.
Does this mean I can’t use a Sig, nope.
Does this mean I wouldn’t pick one up in an emergency? Nope.
But it does mean that I’d trade it for something else. And quickly.

As to LE agency armories, I can provide a little insight on this, it starts getting bad, the armories will be emptied by the Officers themselves.

This won’t be like “The Walking Dead” where they go in after some calamity and find dozens of guns just hanging in the racks and hundreds of rounds of ammo. There may be a few initially, but honestly, most of the spare guns will be issued to Officers/staff during the beginning. It depends on the crisis of course.

My first department, on 9/11.
The “armory” consisted of 7 shotguns and one 9mm carbine.
They normally stayed at the station. That day, each car got one long-gun and there they stayed for the next two weeks.
There were several cars that the Sgt’s brought their own carbines in, knowing that we didn’t have enough.
There was a single spare handgun in the ‘vault’. It was given to our dispatchers, just in case.

As to ammo, most ‘armories’ are sadly lacking in ammo these days. Our local PD/SO have to scrounge ammo to qualify generally, budgets being what they are. My last two departments were the same. Again, any spare ammo will be issued/handed out in-house.

I have long said, “Is gun, Is shoot”. I can use almost anything and have.
Thankfully we are at a point where we can make the choices for ourselves to arm prior to having to scrounge firearms or ammo for real.

And as the owner of a gunsmithing business, I realize that my place is a first line target for the bad guys.
It starts to get weird, I’ll do like I’ve done in the past, and remove the important items for safekeeping.