I think there is no crypto currency that can surpass the value of a bitcoin. Bitcoin showed possible outcomes in this crypto world, it has scaling problems, and as ethereum dapps are created in the gambling space , that market cap will be added to ethereums.
That's just gambling. What about others? a lot more capital has to be pumped in to the cryptocurrency system.
If history is any indicator, not every pioneer in a field would be the one to reap the benefits of large scale adoption. Usually the innovator is the one taking the risks, educating the public, but then a competitor with a better business plan comes along and leaves the innovator in the dust.
I think Ethereum is trying to do this with bitcoin, but I don't think it would succeed. The full potential of the crypto space has yet to be revealed, and maybe one of the businesses that used ICO's to fund themselves will provide a better solution to tackle word's problems. We shall wait and see.
But BTC and ETH fill different roles and are not meant to be mutually exclusive.