I already said most of that, by saying that buying and selling is what defines what fork has value. But unless you define value by the Twitter noise, the only way to objectively measure what the economic majority values, is to look at the heaviest chain. If Satoshi wakes up from death or whatever, he doesn't need to open twitter, not even GitHub, he just needs to run his node, and check the heaviest chain. The heaviest chain tells him everything he needs to know. As a matter of fact, even Knots could objectively tell if the economic majority is with them or not, by watching either signaling or watching the two forks (since they are a superset of Core). So again, the ONLY objective measure of what bitcoin is, is the heaviest chain compatible with an old node ... In fact, even if the heaviest chain is not compatible with your old node and your node can notice a much much longer chain but isn't compatible... Then you ought to double check because you might have a bug that the world decided to patch with a hard fork. Ultimately, I actually think Bitcoin Core should include such alert for users to go manually judge which fork they need to follow, and whether their old node is actually following their intentions. But I think most people agree with this, but just hate to admit it. Consider this, if majority of economic nodes decided to run older nodes, and miners subsequently started to steal taproot UTXOs, is that a hard fork? Not according to the majority, and not according to Satoshi, so you are left on a fork that doesn't even agree with Satoshi... So now what defines consensus? By definition consensus has to be reflected in the demand and thus in the heaviest chain Of course this is not something that can be settled in a day or a week ... But after a month or two, someone will give up and follow the majority of change the proof of work or checkpoint a block etc... regardless they will have to become a minority fork and as I explained above the majority fork isn't necessarily invalid according to old nodes.

Let's be perfectly clear, we don't even know if the majority of economic nodes enforce segwit... We have reasons to believe they do, but really we don't know. All we know is that miners reject invalid segwit, and any invalid segwit block seems to never be built on top. I am not saying you are wrong, I am saying that after a certain scale, all these social coordination tools break down entirely, and we end up with nothing useful except what miners claim and evidently do.