I think the bitcoin cryptocurrency money is one of the greatest financial bubbles of all time.
If you think something is not that much stable as others, then it is a bubble, if this is the case you consider I must oppose this. Reason is, there are so many big differences between crypto world and that is of fiat. But the one and the important is, these coin prices dont stable. They are always going up sometime and then declining with much acceleration. So yes or no, it differs.
In very beginning when bitcoin was not as such popular and when the investor of bitcoin were few then the significant increase in the price of bitcoin in a short period of time would consider as bubble, but in current time as the bitcoin investor are spreading throughout the world even in backward countries people are now taking interest in bitcoin to invest their money there. Therefore i think the current increase in the price of bitcoin cannot be consider as bubble, but it is because of the increasing demand of bitcoin by the investor and hope that this trend of increasing the price of bitcoin will continue for a long time, because still bitcoin has too much potential to increase it price because of the increasing interest of the new generation and young investors.