Seeing how well Ethereum is doing in the last months, there is no doubt that it's capabilities could be expanded in order to make an operating system powered by Ethereum. After all, it is a decentralized platform for applications and it is often called the Ethereum World Computer.
If a decentralized operating system could be made from the Ethereum platform, things will get pretty interesting by then. Imagine an operating system with the ability to repair itself with the Ethereum network....
There are many possibilities and I think this could be a great idea. Don't you think?