agreed, in fact I would say it doesn't simulate real world anything.So, D&D isn't a true wargame where you're supposed to emulate real-world warfare.
my thing is I want my players to feel like they have agency in effecting the odds, and an understanding of said odds. I don't want them to make choices blind I want them to be informed.Generally, if a war is happening and it doesn't directly influence the main focus that the party is going through, it gets handwaved in a sentence or two. "The Ilustian army is in war with the Crote army." At that point, its minor worldbuilding.
To go with my Star Gate concept, I want them to understand why a GHoul war ship showing up over earth is a disaster in season 1 or 2, but a fight in season 7 or 8 and you might feel sorry for that ship if Atlantis is cloaked in the san fran bay. However that same ship showing up to Talona is never a threat... and if it is that is a clue something is VERY wrong. Can the Asgaurd beat the Ghoul, yup if they send there forces, but then they will lose the war with the repilicators back home.
I think I have heard way back in the 50's gary called them artillary like a big gun.My own theory: in a world with DnD-style spellcasters, they replace heavy cavalry as the core of the armies of the world. Whoever can bring the most wizards to the fight usually wins, so each kingdom is always looking for ways to get wizards (or other full casters) on their side.
yes having mercenaries is a big boon. Especially if adventuring parties aren't limited to PCs... "Oh wait that side has 4 or 5 groups of weird people with levels and creative minds... that could be a problem"The easiest way is to just pay them a lot of money and not bother them when you don't need them for warfare.
MAgeocracy happen for a reason.Over time there's be a lot of overlap between the nobility and wizards - magical bloodlines would drift upwards, and nobles' children would be sent to magic school.