Yes! It will be very difficult for ETH to beat Bitcoin even in the next 20 years, this is because ETH has big rivals on the smart contract technology. Main while, when you look at Ethereum and Bitcoin, it very obvious that their goals are largely different.
For example, Bitcoin is a global currency which allows individuals to own their own money (without having to rely on national banks). ETH serving as a building platform for dApps/smart contracts, which allow it to send tokens that represent values.