The question of who controls Ethereum always depends on the technical infrastructure. Recently, it is worth looking at a proposal put forward by Vitalik Buterin: breaking the centralization among block builders. One of Ethereum's main issues is that certain players have too much power in the block production process. Buterin's plan specifically targets this. Reducing such concentration in the network's structure is critical for the Ethereum ecosystem to truly be decentralized. This imbalance among block builders can affect the network's health in the long run. In other words, the question of who controls Ethereum is actually shaped by these kinds of technical decisions. Buterin's move is also closely watched by the community because reducing centralization is one of the fundamental principles of crypto philosophy.