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.
Perhaps I will agree with you, time of mad growth of the price for cryptocurrency already passed. It will be very difficult to make 100k of $20 in 10 years. More precisely I think that it cannot be made.