Bitcoin's value is not entirely tied to its technology, but also to its network of users.  There is a big network of physical exchanges that let people buy/sell fiat for bitcoin.  This has a lot of value because most people will see bitcoin as the first cryptocurrency they deal with.

The use-case of bitcoin is currently value holding and will soon become a currency for DAO's.

Other crypto-currency will probably increase to a bigger market-cap then bitcoin in the future, simply because their business has more growth potential.

At the end of the day, we need to build bridges between all decentralized projects to make it easy to build projects on top of these foundations...  I personally believe that bitcoin will never fall to zero simply because it will be the currency in a lot of DAO's in the future, while the coin of each DAO will operate like a "permit to do business" in the DAO itself.

Thanks,
Steve