I think it's absolutely possible even without making an appeal to bearish speculative phenomena driving the price up artificially. If one can consider that blockchain technologies might replace currently deployed commerce systems then one can approximate their overall value (compared to world GDP) and even though it seems extraordinary-- Taking the total number of possible bitcoins as a index variable, it's possible that BitCoins could normalize at 80,000-70,000$+ but that's if we're real optimistic about the whole thing.
I think a buy and hold strategy is appropriate here. Decentralized tech is just in its infancy. Let's see what the next 5-10 years hold!
It's like owning stock in Wal-Mart in the 70's. The value isn't in the overall success of the stores or the real assets of the company-- It's in the companies retail and distribution model. It's the same with cryptocurrencies. Their value at exchange is probably mostly speculative but their real value is in the technology itself. There's a lot of ways of fathoming the whole thing though.