Bitcoin I'm invested in. With quite some money to be honest. And I plan to hold it for a long long time.
Ethereum however is something I like to trade, to make more BTC. But I will definitely not hold it for years or so.
Ethereum is extremely centralized, the lead developer is in bed with politicians and probably also some agencies. It's heavily supported by CEOs, who try to get more and and more control over it. And Vitalik will give it to them. Regulators have an eye on Ethereum as well. If it should be declared as a security many of the big exchanges will probably drop it. Furthermore there are lots of pretty strong competitors who will fight hard to replace Ethereum as the lead smart contract platform. Beside many technical issues and a very unsecure programming language (Solidity) there is also the big no go of immutability (DAO desaster).
Sorry but Ethereum will get pushed by the incumbents of the actual system, for a while, until they drop it like a hot potato.
Bitcoin is the only real censorship resistant Coin and Blockchain out there, who can be adopted by anyone in the world and therefore reach some real high value in 10+ years.