Ain't nuthin' perfect.
How many years did we consider the 1911 to be safe, even carried in Condition 1? Colt started selling 1911s on the commercial market in 1911 or 1912. The Swarz firing pin safety mechanism wasn't introduced until the 1930s, it wasn'r ever used on all models, and it was dropped at the start of WW2 and never reintroduced.
The Series 80 firing pin safety system was introduced in the early 1980s, 70 years after the 1911 first went on sale, and even now the Series 80 system isn't used on all Colt models, and many makers of 1911s don't use it at all. For years there was an Internet article that purported to "prove" that a 1911 would not fire when dropped in its muzzle. That was accepted as gospel and cited by many people (including me), until a few years ago when Walt Kuleck and Drake Oldham performed their series of drop tests and showed that a 1911 WILL fire when dropped on its muzzle. Walt's testing convinced me to only carry 1911s with a Series 80 firing pin block.
But even that only addresses a muzzle drop. The 1911 trigger has mass. I wonder what would happen if a 1911 were dropped at the same (or similar) angle as the P320?
To me, what this situation demonstrates is that it's impossible (in practical terms) to test guns for every conceivable drop attitude. Am I going to take out a 1911 and start dropping it at different angles? Heck, no. Nor am I going to stop carrying and sell all my 1911s because of the remote, mathematical possibility that there may be some combination of angle and orientation under which even a 1911 with the Series 80 firing pin block might drop fire. I'm going to continue to carry 1911s, and I'm going to continue to do my best not to drop my firearms.
I don't have any quibble with the fact that SIG tested the P320 to the industry standard and stopped at that point. Testing costs money, and no company is in business to waste money. (Well, with the possible exception of Tesla.) If I have any issues with SIG, it's with the fact that they seem to have become aware of this as a problem early enough to have changed the design of the pistol they submitted to the military, yet they did NOT immediately change the pistols in commercial production or immediately issue a recall. They kept quiet until someone let the cat out of the bag, and now they've been caught with their fingers in the cookie jar.
That, to me, does not speak well of SIG. Not the fact that the issue arose, but the way they approach (not) addressing it.