It's all still waiting to be figured out, but BTC has the job of upholding crypto's principles in a way others don't.
It's like royal brothers. The one waiting to be king has to be a stiff. All the other ones are free to go and fuck winos in the eye socket. No one cares what they do.
If Bitcoin ever did this many would leave crypto all together and never bother returning.
Perhaps some people would, but I suspect they also might just be a small minority like the BIP148 contingent -- a small uncompromising group who is willing to fork themselves off the network and into obscurity.
If it can be coaxed into doing it that means everything else can and will if it suits people who are rich, powerful or persuasive enough. It would be back to square one with a whole lot of money, effort and energy wasted along the way.
Immutability and decentralisation will ALWAYS be attacked as hard as possible by tossers who want short cuts. The people resisting know perfectly well that that's its only real value proposition.
The biggest mistake that people make is assuming that Bitcoin is immutable. It's not, and never was. This is a crucial mistake people make in their assumptions about pertinent game theory.
Bitcoin's design puts transaction reliability in the hands of miner incentives. I think Rubin made an interesting point about miners negotiating with one another about whether to build on the most recent block or to mine selfishly. We like to think that Bitcoin's incentives are perfect but there are surely situations where miners could maliciously profit (and have maliciously profited) from reorganizing the blockchain. When we think about smaller reorgs under this incentive set, we just consider it orphaning.
So, there is an element of cognitive dissonance here and sadly, that's what this boils down to. Do you support free markets -- where miners can reorg the blockchain based on free market incentives -- or do you think these "hardliners" can and should pressure miners into ignoring short term market incentives in favor of
their desired outcome?
This is the age-old question about long term vs. short term miner incentives. It really can't be answered with any level of certainty. I will say that I'm skeptical of people who think they can predict how the entire economy of Bitcoin users would react to any given situation. I'm agnostic on this question myself.
Do I want to see coordinate blockchain reorganizations? No, but if it happens, it happened because of Bitcoin's economic design -- full stop. My suspicion is that the market would understand this far better than ultra conservatives who would assume "Bitcoin is dead" because of a reorg. Those people are more like Bitcoin Cash supporters who sold all their coins because of Segwit activation because they fundamentally misunderstood Bitcoin's economic incentives. They'll be forked off and the rest of the network will move on without them.