Many people have been calling this a bubble for a long time. Nobody cares while they think they are making money though.
Yes, it might not even be a bubble. It might be the end of bitcoin and the adoption of some other criptocurrency that doesn't take that long to confirm small transactions. But, during the times, people might not recognize the bubble, and people might call "bubble" things that weren't.
As for the end of bitcoin/cryptos - I hope not. A bursting of this bubble is hopefully just a rite of passage so that they can mature and gain adoption. Basically everyone knows what they are now.