rules, they cannot force a split of the chain, and must adopt it. The users will have to accept it too,
whether they are aware of it or not.
That is the point: users who do nothing automatically accept any soft-fork type of change, even if they are unaware of it.
Yes... that is the point... so long as the change does not undermine the currency (store of value) in any way, then it can be made without any significant objections from users. Many technical changes are going to result in no meaningful perceived change.. but if there were an attempt to change something fundamental, such as the number of total coins (or the governance to allow for easy take overs), then users may well decide to vote with their feet.
Take my favorite example: postpone the next halving by 2 years, but then shorten the halving time to be every 2 years instead of every 4. This change would not increase the 21 million limit; it would keep the current rate of inflation until 2018, but the inflation would drop much faster after 2020, so that issuance would be complete in half the original time.
Would this change be "good" or "bad"? All the miners should love the idea, since it postpones the 50% drop of revenue next July. Holders who were hoping to cash out in 2019 may hate it, but those with a longer outlook may love it. And the miners could point out that, without that change, many of them would have to shut down, which would cause the hashrate to drop, which would be bad for bitcoin's security and very bad for its image...
If this scenario were to occur (which is highly speculative - and likely would not occur), this kind of change is a significant material alteration of the value that would likely cause users to lose confidence in the value of the currency (storage of value) because fundamentally (in the short term) it has just been manipulated by a small segment of the population... again, this is really speculative, very unlikely that any good intended group would attempt such, and because of it's high degree of improbability, not really worthy of an indepth discussion.