Wow, that article is the worst piece of bitcoin-bias I have yet seen I think.
Yes. And I enjoyed wallowing in it.
The only way an alt-currency survives is if it has some new feature that is impossible to add to Bitcoin.
Correct.
One point which they did not highlight enough is that because cryptocurrency is software it is much harder for altcoins to displace bitcoin, which is very different from competing manufactured products.
Consider supercoin which has some radically better features than Bitcoin. Because Bitcoin has over $1bn riding on its success there is a significant investment by all the people who use it, own it, mine it, and otherwise profit from the ecosystem. So there would be huge incentive for Bitcoin dev to clone the software changes which make supercoin so super, even if it means a hard fork. Such a hard fork would be tolerated as all bitcoiners want to protect their own interests. As soon as these features are released in a new bitcoin version, then supercoin becomes irrelevant.