Firstly bitcoin is not a bubble. People want to buy bitcoin because bitcoin have some special features and it is future money in my opinioın. So people buying that so bitcoins price continue increasing. We can not say that a bubble. If you can say bitcoin is a bubble i think gold is bubble for you also. Gold is only a shining metal with yellow colour .. 60 70 percentage of coins will die in the future because they are scam. but 40 percentage will continue their lifes.