If that is the case as you said ETH should have taken over now.
but the fact is btc is still strong in the lead, we will never know the extent of development that will occur in altcoins, but still the one who will be at the top is btc.
You mean the value of Eth should have taken over Bitcoins? Well that can never happen because Eth are more in number and will always have way lower than the value of bitcoins.
If you meant that the total market cap of Ethereum should have overtaken Bitcoins then actually Ethereum has done pretty solid and Bitcoins are like 5 times more market cap than Ethereum but we know the market cap for Ethereum is increasing at a high rate as compared to Bitcoins.
I would agree like others that BTC remains superior and dominant as ever but there is a serious and real chance we might see Eth crossing the market cap of bitcoins in next few years.