If Bitcoin has no value, for sure it won't increase as they have now, and it won't stand long for more than 10 years. But the price value of Bitcoin at the moment was too huge, it means many community all over the world embraced the good features it has and the possible benefits that We could get from it. And it possible too that it can be the world currency someday.
I think what you are saying is the price right now, it is true that its value is huge but it differs for every investor. If bitcoin really has a value, an intrinsic value, then there would be no way that we could put the price of it beside USD. Do you see the price of btc without the fiats? No, that is what we are talking about here but that is the same with fiat, it is just a paper told by the government that is the currency, designed it, print it making us believe it is worth that much, it is still a paper though.