That's more about the technicalities of a normal fork-split situation rather than a social-engineered takeover attempt.
You're using double standards acting like Blockstream pretending they should have dictatorship over Bitcoin isn't a social engineer takeover attempt itself. Devs don't control Bitcoin. Devs are politicians and we don't have a one party system. If we did, Bitcoin would be centralized and worthless. Whoever wants to rage quit because they don't get to be dictator and do everything their way, let them.
If you don't like how bitcoin is you create an altcoin. There is no dictatorship involved. You can change from a single parameter to every parameter.
If you want to change bitcoin itself there is the strong possibility that other developers might disagree if you propose something that is not optimal. Since you can't have multiple implementations for every single point of disagreement (multiple forks/currencies as a result / corrosive to trust in the currency) it is logical to first find a consensus. Is that a "dictatorship"?