Actually I do not think bitcoin is a bubble
You have to think about the development of currency from ancient times:
bundles for exchanging cattle for a dog, changing buffalos for pigs ...___ things to change into consumer goods ___ gold coin ___  metal money ___ electronic money ___ digital money
You see the process of development, and digital money is the evolution of humanity as information technology evolves
A lot of people making money  and get richer by bitcoin  it is not a bubble because big companies are embracing cryptocurrencies,It is a means of rapid payment support in modern society today. Despite the price fluctuations as it is in its infancy and development stage, I believe in the future of bitcoin.