well we cannot say that ethereum is the future of cryto and bitoins are not , ethereum and many alt coins were formed after the success of bitcoins , wehen bitcoins ose to $2000 , bitcoins now give a big amount of advantages . It has a bi community behind it that is supporting bitcoins , the number of users are also increasing day by day , this helps bitcoins to become more powerful .
but yes no one knows what is in future , ethereum has potential to come up but for them overpowering bitcoins would be like impossible .