Of course, everything can be. Perhaps these coins or at least one of them will rise in price just like bitcoin. Although, the chances are not so much. I think that the more the crypto currency develops, the less probability it will be to increase its price by millions of times. In my opinion, the period of the "wild" crypto currency is already passing.
I have to disagree. The overall market cap for crypto is very small when compared to the market cap of more traditional investments, like stocks and bonds. If the market cap for crypto can get into the trillions then many millionaires will be made.