They signaled support for it, but when push came to shove, they bailed. I'm not saying 51% of miners decide what the rules are. Suppose you had a Bitcoin fork

They signaled support for it, but when push came to shove, they bailed. I'm not saying 51% of miners decide what the rules are. Suppose you had a Bitcoin fork that had 80% of the hashrate. How long would that situation need to persist until the major network participants decide to call that fork "Bitcoin"?