The reality is that people sit together and try to make a deal that all parties agree on simply because disruption and uncertainty is not in the interests of any of the parties. This doesn't change the fact that the parties do not have aligned interests and therefore its a constant fight everything is slow and expensive because of that.

Kinda funny how this problem was solved before ETH even existed simply by removing the incentive for the hardware operator. No block rewards and no fees to collect aka no reason to fight over it. The only people who run the hardware without getting paid for it are the people who want to use it. They have aligned interest like a fast and cheap network and fast update cycles. And ofc no one who has to pay for the hardware and energy has any interest in PoW.

It is necessary for some miners to choose to use the post-fork software in order for it to work, but miners take on the task of mining due to financial incentives, and the users ultimately control those incentives. Miners only have a choice in the sense that they could collectively choose to abandon their profits as a matter of principle.