I believe that they're popular mainly because well it was the first of all cryptocurrencies to be made. Honestly most of the other coins are scams and greedy ways that the developers make money. The only other coin I can think of that isn't a scam are dogecoins! What do you think?
Nail on the head, this is pretty much the only reason. bitcoin is trusted because ozf its age; essentially no one here feels there is a major flaw lurking around waiting to be exploited, to ruin value. bitcoin is far from the most advanced coin on the market; without a doubt at this point that distinction would have to go to Ethereum. not an eth fanboi, but in terms of raw venture capital applied to development of the protocol, there may be more investment/innovation in eth at this point (ICO scene) than there has been over the much longer life of bitcoin.
we are riding trust now, and not innovation. there was a time when I could have justified the price given what bitcoin was presenting; not that the space is saturated, i can't really see myself a reason that bitcoin should be on top, save age, and level of adoption.
and that we are riding trust, when we degrade it as a community (the forks) the price suffers accordingly (observe
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