ETH may bring higher returns over the next 10 years but bitcoin is far safer as an investment due to a much lower supply & its decentralised nature. ETH has much more points of failure, it’s a far riskier investment. It all depends what your level of risk is & what you’re looking for.
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.