For starters, bitcoiners would have to find a way to get rid of all altcoins, present and future. Including AppleCoin, WellsFargoCoin, WalmartCoin, ...
Perhaps they can find corrupt congressmen that will accept bribes in bitcoin and pass laws criminalizing the use of other coins?
LOL. So we would have to prevent something that doesn't exist yet? How do you know we haven't already done the through the magic of "market incentives"? If those corpcoins were truly decentralized, distributed and peer-to-peer, they would convey no advantage. To the extent they would convey advantage, they would be to that extent less popular. Which may be why you don't see any.
So I would have to wait an infinite amount of time for you to admit you were wrong?
As for present alt-coins, why do they make you doubt Bitcoin? Success always has imitators.
Altcoins are the safety net for crypto-currencies.
When some idiot tries to corner the market on Bitcoin simply trade into an altcoin.
Crypto-currencies are not all about Bitcoin.