Keep in mind that warriors throughout history have often chosen weapons because they are better at killing the opposition (the dpr of real life) this was mainly in answer to the equipment or tactics/formations the enemy used. You bring heavy armour we will bring hammers because they will do more damage for example. Damage was a concern so a character aiming for more damage is not for the most part aiming to kill "verisimilitude" (I hate that word it has killed so many good mechanics and taken so much away from martial characters, during playtesting it became shorthand for lack of imagination and I refuse to acknowledge what HP are instead of just meat).
This isn't entirely true. I mean, yes weapons were used that were good at killing the opponent, but it's not like they went all "Deadliest Warrior" and did evaluations of every weapon design to measure the total area damage in an attack. People didn't say "Well, the greatsword cuts 1/4" inch deeper, so we'll use that from now on and no one uses an axe!" If a weapon could kill, that's all that really mattered. Didn't matter if it was a scimitar or a long sword. Rather, if you look at historical weapons, it was most impacted by culture and region. If you're going by your logic (weapons were chosen based on the "real DPR"), the most used weapon of all time was the spear, so should the spear have the highest damage over any other weapon? (Yes, I know WFRP 1e does have the spear as the best weapon).
Even with armies of the same region, we see different weapons used for cultural reasons. Some tribes used axes mainly, some used swords, some used spears, etc etc. All were deadly. So no, I disagree that warriors used the "highest DPR" weapon. History doesn't support that, largely because there isn't any significant difference between an axe and sword in the ability to kill a man. And that's my point. There shouldn't be in D&D either, because then you end up with metagaming choices of everyone having a greatsword over a great axe. And clearly our historical examples prove otherwise.
Also, I'm sorry you hate the word "verisimilitude". Probably about as much as I hate the term "player agency" (which has been used all to often as a way for a player to say they should get whatever they want regardless of what's going on in the game world or how the DM is running the game.)
I heavily doubt that any military force in history ever choose their weapons because of "coolness". While culture played a bit into it people chose what was effective, available and economic. So this "metagame" thinking was exactly what happened and still happens in real life and everyone who chooses an inferior weapon because it looks cool ends up dead really quick.
So what really breaks verisimilitude is the knife master running around and being as effective on the battlefield than the guy with a longsword (unless when grappling) or that a guy without armor being as hard to injure/kill as someone with heavy armor.
I didn't say the military choose coolness, I said some people (which includes a lot of people not in the military) choose weapons based on how "cool" they think it is. And that's true. Culture didn't play "a bit", it played a lot, about as much as environmental factors. Seriously, go open a history book on the various cultures and the weapons they used. There's a reason why every culture had their own favored weapons, even cultures that were in the same region and faced the same types of enemies (like the Franks vs the Goths vs the Romans).
Also, I don't think you really know how melee combat does work in real life. My argument is to base the damage off of PC skill. And I'm here to tell you, a skilled person with a knife would wipe the floor against a lesser skilled guy with a sword because we can see it happen over and over in demonstrations. Same with unarmored against armored.
So my point stands. IMO, using metagaming to always choose the greatsword over the great axe not only takes away from verisimilitude, but history supports the opposite (and explains why it takes away from verisimilitude because it's not realistic). Metagaming, by it's very definition, can't occur in real life because it's
real life.