Except that it you read the lore for KoW, both 2nd and especially 3rd ed, they aren’t fighting like those examples. They aren’t marching around shoulder to shoulder in tight ordered formations like phalanx or the legiobs. By the lore they are using looser shield wall styles of fighting, or are even just a ragged mass of warriors. The ranked up miniatures are abstract representations not literal. Which is likely one of the reasons mantic encourages reduced model count and multibasing. Because it makes the visuals more appropriate for what the unit is supposed to be.
Add to that the Lore’s description of the setting, where most of pannithor exists in some variation of feudalism or tribalism, conditions where the armies can be described as ‘retinues of retinues’, being comprised of many smaller bands drawn together into a larger force. In such armies the smaller bands usually fought as a single unit semi-idependantly (albeit alongside other such units in the battle line) not as part of the sort of massive organized formations you describe.
Nor does stuff like erwhon for the kind of warfare I am speaking of. Those sorts of rules (including stuff like SAGA) are for skirmishes, not actual battles. They are for the special operations, the raids, the scouting, etc.What KoW has Vanguard to fill. But those rulesets can’t fight battles involving more than a few dozen men, certainly not the hundreds of Men that constitute a normal sized battle in history, much less the thousands of the large scale (mega)battles in history.
further, the setting is inherently unrealistic. even ignoring the whole dragons and magic and monsters beings stuff, it is a setting where 10th century shield walls coexist next to 15th century arquibuses and pikes which coexist next to 17th century plate armor which coexist next to 5th century BC chariot archery. a setting where this technology and ways of warfare have remained static for millennia on end, by cultures that have remained basically the same over that same time.
Short version? The units in the game are representational, but they probably don’t represent the kinds of massive formations you claim them to be.and while the smaller numbers might be unrealistic, they are by far the least unrealistic element.