Welcome to the internet. It IS the main area where people DO go to argue. It's faceless and those with an agenda can post to their heart's content on all that they see as wrong in the world - without having to see the actual facial expressions of others. It's all limited to the written word - which is a field for propaganda at any time.
What we often discuss are the details of fact, which are often filtered by our own understanding and experience. Me - veteran who served - and I know that the Geneva/Hague doesn't stop much in the way of bullet design, nor does it actually need to.
While the language is often quoted, the actual application is one the US voluntarily abides by. We didn't sign anything binding and there is no legal remedy if we were to start shooting full lead hollow nose projectiles. The reality is that most of the targets we do shoot at are behind something - because even the most primitive tactical education in the worst trained force on earth knows to find cover when the bullets fly. Cover = hard barrier, to stop bullets. We have to penetrate hard barriers, whether expedient, or worn as equipment, or used as armor to protect the enemy. A hollow point expanding bullet would be flattened on impact and have very little penetration. Major fail in combat. That's why we stick to FMJ and use penetrator tips for 5.56.
We are NOT prohibited from using open tip ammo - what we do is use only that ammo not specifically designed for expansion. That means open tip ammo that is designed for aerodynamic purposes IS legal under the Laws of Land Warfare, it that was approved back in the early 1980's. The design intent - of Sierra MatchKing bullets, to be precise - was to form them entirely the opposite of previous ones, by punching a gilding metal jacket around the core base first, leaving a light jacketed nose empty for ballistic and production purposes. They have been Olympic grade accurate since the 1950's and are the first choice when shooting long ranges. Being accurate also reduces the likelihood of an innocent bystander being hit. They are our first choice of use in long range precision and CQB ammo where penetration is a known factor and usually not an issue.
The small highly trained shooters in the American Armed Forces get OTM, the general combat units in bulk get FMJ or penetrating ammo. As long as we adhere voluntarily to the Accords we won't see bullets with formed jacket petals and a hard heat resistant polymer tip to aid in expansion. For most intents and purposes in the military, we don't NEED them, either.
That's what is fun about the internet - so many in America have no idea of what is going on now as there is only one in one hundred who have served, unlike when I was growing up in the 1960s when one in ten was a veteran and likely to have been in WWII, Korea, or Vietnam. The public is pretty much completely out of touch on military matters and ammo is certainly one of them. The problem is that one's mans misinformation is another's trolling - so we try to keep an polite tone even when we are handed crow over it. It's the youngsters unsure of their place in society who strive to prove who's the more socially ranked. And the internet is exactly where some go to find their place, unfortunately.
They won't join the Armed Forces to discover what they don't know or can't really do, which leaves them with some interesting notions.
Geneva, not. Hague, not hardly, Just voluntarily. OTM, issued for decades. Penetrator ammo - standard issue. Not "armor" piercing but the ATF is politically controlled and that is where they are tasked to be a problem. They were never originally an enforcement organization - just a tax collector - and the reason for the NFA was an anti gun measure we've long needed to abolish.