EzekielRaiden
Follower of the Way
Then why don't players have lair actions? Why don't monsters have Vancian spell slots?The rules work the same for both of them. You can even have full PC sheet for a NPC or have a player to play a "monster" represented my a monster statblock. Only think that is different is who controls which statblock, but that doesn't affect the rules.
Your choice to pretend that these things are irrelevant is just that--your choice. They remain quite relevant to anyone actually looking at the system as a whole, and anyone actually wanting to solve the design problem of "how do we make good design for social encounters, as opposed to the many types of bad design"?
This enforcement of perfect mirror consistency between GM-run entities and player-run entities is precisely what forces such awful design. Ditch that seriously flawed requirement, and whole new worlds of design become available to you.