You are objectively wrong, at least the summing up of it… and some other things, but we could be here for hours dissecting everything wrong but we’ll stick with the “bosses are big mean enemy”. A Boss is in charge, weather weaker or stronger than the enemies you face leading up to said boss.
Lets pick the Inquisitor Boss trailer
Champion: Appears in Every Battle, Mid-Tier Threat- Appears mostly in Groups
Commander: Gives Orders to Followers, Boosts allies, Formidable in his own right
Villains: Very Powerful (appears on his own), Can Spawn Anywhere Randomly, Possess unpredictable abilities
Elite (Appears to be Demons): Extremely powerful abilties, Brings Extended Battles, Rare and dangerous
Boss: Considered exceptionally fatal, Appears only in special battles, Unique gameplay Mechanics
All the examples they gave are capable and able to give commands to underlings, every single one. A Rat Ogre barely has the attention span to remember what it was told a few moments ago, same goes for Stormfiends and Trolls. While Chaos Spawns are to insane to function normally in society.
It should be noted that Stormvermins aren’t so much leaders as they are just higher in the caste system of the Skaven then lowly Clan rats or Slave rats.