Ethereum is the second largest blockchain platform by market capitalization after bitcoin and is the best and more promising choice among other Altcoins, and besides that many traders believe Ethereum is a good investment compared to other cryptos.
So I think Ethereum will remain the king of Altcoins and will continue to be popular and the best among other altcoins, and only able to compete but not completely replace its position.
I totally agree. Many developers are already familiar with Solidity and the whole ETH ecosystem. It would be VERY difficult for a new altcoin to surpass it.