Check out the link below for major bubble of the past...one MAJOR difference when comparing it to cryptos is the time frame. The bubble of the past took years to build up to the highs( 5 plus years)...and 1-2 years to fall to the bottom. If you think cryptos is a bubble...then you are saying that all of that happen in just a few months...something to consider.

http://www.thebubblebubble.com/next-bubble/