Ethereum has intentional soft and hard forks; whatever that process is, that’s it’s government. Whether that government chooses to address problems which challenge Ethereum‘s legitimacy is up to them.
I think that’s the right follow up question to explore - what establishes political legitimacy. Or perhaps more accurately, what best establishes political legitimacy. There’s arguably a vote in the sense that users of the network choose which fork to adhere to. This isn’t a perfectly distributed vote; you depend on the miners, the validators, the client developers, and the exchanges to establish a concept of the “current fork.” (God help us if all the exchanges ever decided differently than Vitalik what “ethereum” is.) Regular users have a minimal voice in that decision, but it’s theoretically possible for anyone to start a new fork and campaign for its adoption.
Personally I think the question of political legitimacy doesn’t make the notion of blockchain governance wrong; it just highlights that the system as constructed may have problems.
In a sense, it sounds like a political party that splits in two. It’s not democratic; maybe it’s technocratic.