I think bitcoin will not be replaced with another cryptocurreny, because if we have to look at the btc price right now; no other cyptocurrency beats it's price. Comparing it to ethereum today, it has nothing to do with price competition which mainly other people have compared it and also speculate about bitcoin's death in the system.
I don't think that there is a lot of money that is being bet on Bitcoin's death, a lot of the money in Ethereum is because of ICOs and tokens that is provides which are typically more ETH heavy rather than anything else. It's a big speculator's currency, and that's mostly why there is a lot of money being pushed into that asset as opposed to somewhere else. Once the Bitcoin community fixes the blocksize it hopefully will not longer be a contest as to what the dominant crypto is.