If a participant is at liberty to suspend the lusory attitude and change the available lusory means, what would it even mean to say that, at some particular time, they have adopted the lusory attitude? This strikes me as a recipe for dysfunction (at best).So where we will not agree is that the referee is, or is solely, a player. It is in performance of their function as referee that they suspend their lusory attitude and make whatever rulings are required.
Apart from anything else, what is the meaning of "are required"? This just seems a version of White Wolf's Golden Rule, or the passage @Bedrockgames quoted from the DMG2 upthread, about departing from the rules if it improves the game.
To link this back to the question asked in the OP, a "game" structured in the way you posit is one without rules - that is to say, without limits on lusory means to which the participants commit (ie by adopting the lusory attitude).
There are some people who like RPGing without rules, and so their answer to the question posed would be there is no need for RPGs to have rules. But we don't need to dress that up in the somewhat obscure language of "rule zero".