When you guys say, "Ethereum will take over Bitcoin as the next viable cryptocurrency" you are hugely mistaken. It's not even a currency to say the least, it just acts like a currency because you can trade it in for bitcoins and also be able to send them, which makes it an asset at the least... An asset that allows you to access the services that Ethereum has the potential to provide.
Ethereum isn't a currency.
You do realise you could easily switch eth with btc in the above statement and it'd work out just as well on your logic? They're both cryptocurrency and both are blockchain assets so it is a bit pointless to dismiss them that way.
But back to the topic, the question is perhaps far too simplistic: "Could ETH take over BTC?".
Assuming it's in popularity and percentage of overall crypto transacts, then personally, can't see it happening too quickly, if ever at all. BTC will almost always be the first currency used by newcomers and it would take a more serious user to consider the advantages/other aspects of using ETH.