Two Sets of Rules, the Good and Bad?

[GooeyChewie]

WotC decided to create Legendary Actions for monsters (an asymmetry) as a metagame balance bodge. Rather than a good solution that sustained verisimilitude while addressing the metagame balance too, it is a sore thumb. Some asymmetry is ugly like this. A type of asymmetry you were not talking about and thus don't see how it relates.

I acknowledge that Legendary Actions were created for metagame balance purposes. I do not agree that this asymmetry is ugly. I find it useful and necessary for the game.

From the monster's perspective, the players also have a metagame balance bodge. They can bring more players! That final boss the DM was planning might have been fine for four players. But when Joe brings his co-worker and Suzy brings a friend and suddenly you have a party of six set to take on that solo enemy, that same encounter will be a cakewalk instead of an epic battle. So the DM needs a way to make up for the party's asymmetrical ability to add more actions via adding more party members.

What, so your argument is that "combat is an abstraction and therefore it doesn't matter what they do, it's fine"? Doesn't sound very convincing to me...

I think the argument is more that all of combat is an abstraction, so criticizing one specific element of it for being an abstraction doesn't make sense. Any particular mechanic in combat should be evaluated on the basis of how well that mechanic accomplishes its goals. Legendary Actions may be abstract, but they accomplish the goal of helping balance single-enemy encounters against party size due to the party-size dependent action-economy advantage the party will have in such encounters.

Giving Legendary Actions to players might sound fun. As a one-time thing it might even be fun, as a way for the players to take down something that would clearly outmatch them otherwise. If it were a standard mechanic, it would just add to the party's action economy, which in turn means the DM would need to account for that action economy by using more enemies or more Legendary Actions for single-enemy encounters. Ultimately adding Legendary Actions to players would only serve to add more actions into each round on both sides rather than to make combat better or more balanced.