Imagine you have created a new social media webapp with a few innovative new features not seen elsewhere. Would that spell doom for a now suddenly inferior Facebook/Twitter/etc. Possibly, but the network effect in terms of inertia and critical mass makes that an unlikely proposition.

Moreover, the driving force behind Bitcoin keeping it ahead of the pack so far is the promise of short/medium term profit as an investment vehicle due to the artificial scarcity of its deflationary algorithm. Other cryptocurrencies are better positioned toward forming a long-term solution as a low overhead global decentralized payment platform, but what they offer is more of a collective benefit rather than a strong monetary incentive to any individual backer/investor on an individual level. (Which arguably is just an emergent property of human greed within the regime of unchecked capitalism.)