Of course there is an endgame, much in the same way everyone on earth demilitarizing would also give you a predictable endgame.  The one party that decides not to is now the ruler of the world.  Bitcoin doesn't appear to have any real Nash equilibrium, so as I said in my post, this acts as a trojan horse to infiltrate nations and create a power vacuum where someone else can just come along and say, "Hey, this doesn't work.  I have a better idea how to run things", and since you have ceded power to a janky, non-functioning computer algorithm, might makes right takes over and they get their will accomplished of a ban on cash and imposed digital only Keynesian currency.

The other problem is that even if Bitcoin did work and have a functioning Nash equilibrium, any anonymous (or pseudoanonymous) digital currency would eventually implode most recognizable known forms of govt in the world.  An inevitable endgame of mostly anarchy in other words.  But anarchy doesn't actually exist, it's just a power vacuum or destabilization scheme where a strongman then comes in and takes over.  When you cede power, somebody else just takes it.

A nice game of, encourage your enemies to adopt Bitcoin first, while whatever nation resists adopting it at all then wins by monopoly of force.