Ethereum is ethereum, and bitcoin is bitcoin. Why constantly compare them and look for a replacement? Nobody says euro is the next dollar?
Maybe they are just talking about talking the no. 1 spot which I think impossible for now.
Bitcoin will be the no. 1 for years, I'm sure with that because it's dominating the market now, ETH is no. 3 now and XRP has a better chance to take the no. 1 spot.