The Cryptocurrency Era is probably just an observation period that will bring something newer, better & different in the coming Years/Decades thus making Bitcoin inferior as an Anonymous but Secure Digital Payment Method.
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More than likely what will end up happening with Bitcoin is that it will be what it is mainly used for now... a very
secure way to transact large amounts of money, but not in an
anonymous way at all like it would be with cash. Not saying that this is a bad thing, and there are possible ways to enable a more anonymous layers to cryptocurrency transactions such as altcoins or side chains... but having Bitcoin as the gold standard to base what everything is priced at is probably the best way to go about things.
Even though some people, such as my self, would rather have the "best coin" to decide on what the majority of people use... that will never be the case. Reason being, is just because that Bitcoin was the pioneer coin that showed us the utility and importance of cryptocurrencies. If people lose faith in having their value stored in Bitcoin, then the volatility of all the cryptocurrency markets would be horrendous and could possibly cause people to lose faith in cryptocurrencies all together.