I do think that the blockchain technology will be here to stay but, while I do hope, I am not sure that the cryptos will stay.
Bitcoin could become the new gold, but, at the moment, I don't see it as a new currency. Why? Do you want to become the next pizza guy? Probably not. Does a company, who sells a good or service, want to take the risk to be paid in BTC, knowing that its value could be 10 to 15% less the next day? No.
Lots of hurdles have to be taken to be ready for mass adoption.
The major issue all the coins are facing now, is their big volatility. This has to stabilize if a coins what to become a real used currency. Coins which are used, as a payment model for using the blockchain will have less problems with the volatility.
So, to answer the question. Yep BTC will stay and for sure the technology behind it. Yes there will come a time of mass adoption of the cryptocurrencies, but we need to give it time and probably it will not be used as some envisioned it!