Bitcoin is more decentralized than Ethereum, because Ethereum still depends on the development of the project and also Vitalic.
If Vitalic is no longer CEO and their CEO is replaced with a new one, of course the future can also change, whether it's good or not,
from this we know that Bitcoin is still much better in the future.
My only problem with Ethereum, beside the fees which can be sometimes excessive, it is the possibility that the SEC and other authorities around the financial world could try to sue the developing team and try to classify Ether as a security.
I know it is unlikely to happen, but in comparison to Bitcoin, it is even harder for the latter to suffer such classification. If Ethereum managed to control the fees of its network to make them more affordable and it was less centralized, I could see a very high growth potential.
If classified as an unregistered security, it may turn into a threat towards liquidity on exchanges...