Yes bubbles happen. What other point are you trying to make? Sir Isaac sold early, got greedy, bought back higher at larger volume, then lost a lot. He knew much about science but feck all about trading and the South Sea....
Even if bitcoin is a bubble and follows a South Sea type chart it still does not help you know where we are on the curve just now with bitcoin other than the ramp up. It could be 200, 400, 800..... Tulips and the south Sea were country specific, bitcoin is global.
Agree we dont know where the top would be , but its a bubble , anyway bear in mind this bubble have been going on since inception , its not new , it was trading at less than a cent , so its an 8 years bubble so far and counting ....
Remember this : "this time it would be different" , thats always the case in every bubble , people think its different but sadly its not .