Government by consensus is not stagnation or immutability. It does not free one from politics or lock the system into a static state of guaranteed obsolescence.
This is simply a centralized power game, nothing else ; business as usual. You will have a hierarchical system with "a leader / king" supported by an "aristocracy of important people" and then the "populace" that is made to cheer for their leaders and to beg for solutions to their problems. You will have palace revolutions, where some usurper will manipulate the populace to replace the corrupt king and his corrupt aristocracy by himself and his aristocracy.
The only thing crypto had to offer, was immutability. Yes, that induces "obsolescence" if it were badly designed, but there is no problem with that. Crypto didn't need to be eternal ; hard forking is the way forward, offering myriads of choices, like in a free market where each individual entity can offer his fork, and see if it works in the market ; not by collectivism into a uniform monopoly that is the feast of aristocracy.
If the rule set is obsolete, let it lose out to free competition, not by collectivist central decision - even if that central decision is bought with votes - voting is a way to buy power because it suffers from a tragedy of the commons problem: if you vote badly, your error is dispatched over all: there is no individual punishment for voting badly, in the same way that there is no individual reward for pouring wine in the big barrel. Voting correctly is costly and difficult, it is not free. It costs effort and insight to vote correctly. This is why a free market is superior over a collectivist voting system: in a free market, if you "vote" badly, the loss is on you, and on you only ; in a collectivist voting system, the loss due to your bad vote is on everyone. This is why voting is the tool of the central hierarchy to keep the power: as the majority doesn't invest in their vote, it is easily bought, and the minority that knows, is overwhelmed by the majority that ignores, to the profit of the central power with the excuse that the "majority" voted.
True decentralisation leads to immutability, simply because if you would have, say, 5 million users, and 100 000 miners in the network, all of them having small fractions of mining hash rate, all of them running hundreds of different node software by hundreds of different teams, there would simply be no way in even contacting them ; as most of them would be anonymous. There wouldn't even be a platform to PROPOSE changes, as there's no way to know if even a very small fraction of the concerned users would look at it. So you see that a truly decentralized system with sufficiently many and small and varied entities can only agree upon an immutable protocol. If a system with a very high "entropy of decentralization" is immutable, it means that a 'true decentralized system" should be immutable, and that if it can evolve, it simply means that the "entropy of decentralization" is too small. This is why I consider that the true definition of decentralisation is the absence of POSSIBLE agreement between more than a few insignificant entities.
"gouvernance" is simply not possible in the limit of high decentralization and hence is contradictory to it. If there can be governance (and governance is needed for collective change) then there is not sufficient decentralization because it means that this is a model that is not possible when decentralization increases.
It is the currently vastly under appreciated next evolutionary step in the regulation of human affairs. Just as monarchy was an incremental improvement over despotism and representative democracy was a step up from monarchy government by consensus is a further improvement an evolution in governance that is currently in its infancy.
There are, as always, only two kinds of human regulation: collectivist ones, and individualist ones. Communism versus free market. Kings versus anarchies. As history has shown, anarchies usually contain power vacuums that install Kings, who abuse of their power to collect more wealth and power, until the system breaks down under its own weight, where a new power vacuum is filled in by another King (whether he got there by violence or by votes doesn't matter). From the moment that there is a uniform system where the minority is eaten by the "will" of the majority or not, we have collectivism.
Crypto could have had a value if it could maintain everyone out of the power vacuum which would be the case if its rules were immutable, because there's no power to be had with an immutable system. It was its only value proposition: it would have been a self-stabilizing anarchy, contrary to most anarchies that are unstable under the power vacuum they create. If within a crypto system, modification of the rules becomes possible, the power vacuum for the power to modify the rules will give rise to the same kind of collapse into a collectivist system as all the rest in human society.
I think one could have designed bitcoin to avoid that, but one didn't. It contains too many fundamental flaws to "stabilize the vacuum" (= immutability). The central developer idea was already a central power, and the economy of scale of PoW will make it an oligarchy at best.
With any new form to gevernance there is inevitable resistance from people used to doing business under the older paradigm. Despots angered at their inability to impose their will have at times violently overthrown democracies. Similarly individuals used to getting their way with simple majorities seeth at the difficulties inherent in building a broad consensus and yearn to use majorities and economic force to subdue their opponents. This ultimately is the source of all this contentious hard fork talk.
This is why immutability is the right solution. There can not be any power struggle, because there's nothing to have power over. If you don't like it, you are free to fork off, and take your followers with you. But you don't impose anything on even one single individual.
I have the impression that "wanting to keep the unity of the chain" looks like having to modify Ford-T in the "ideal car for everyone", and then the dispute goes over how we have to change the Ford-T wheel, how we have to change the Ford-T engine, and we have to come to a "consensus" over what car is now the best car for everyone. No, it is much better that if someone has a better car in mind than the Ford-T, he builds it, and puts it on the market, in competition with the Ford-T. And if 10 people have 10 different ideas, they make 10 different cars out of the original Ford-T and everyone picks what he wants. This is the "individualist" / free market approach, over the collectivist "all together in unity" form. In the first approach, there is no power game, there's just the market. In the latter, ALL is power game.
If crypto is well designed, it leads to immutability, so there's no power struggle possible. Those that want to do so, exhaust themselves without arriving at anything. They should hard-fork and test their ideas in the market, not try to get "a large majority" on their side.
There are already a lot of investments made and companies that wouldn't be happy at all.