You say "miners" like they're a union with a spokesperson. They're not; they're thousands of people spread across the world, with different agendas.
Miners who refuse to adopt the new PoS system have the right to not upgrade to it. At that point, the system "forks" (the article calls it a 51% attack, but I think that's a little inflammatory). This literally already happened with Ethereum and Ethereum Classic; Bitcoin and Bitcoin Cash. It isn't a new situation.
The reason why some miners are dissenting this change is, first and obviously, because they disagree with it. So, why not just fork? Because no one talks about Bitcoin Cash; they talk about Bitcoin. They want to stay on PoW because it will return the best revenue for their mining operation, but if they're busy mining a coin that has little value, that also hurts their revenue. In other words, the only way for them to win is to get the community against the change, which is a losing bet because the change is widely supported.
People are free to disagree with and act against the developers. That's more than you can say for, for example, the United States Government; if I disagree with tax policy or federal monetary policy, I (may) have the option to leave, but changing the system would take a lifetime, if its even possible. Creating a new system without moving countries would inevitably end with the police at my doorstep.
Miners want money. Ethereum, like every currency, is worth what it is because of people. The value of Ethereum goes where the money velocity goes; in other words, where the users go. The critical question is not what the developers or miners support; its what the users support. Well, barring any major conflicts of interest, they'll/we'll probably support the developers; their power comes directly and only from the trust that the collective democracy of ethereum's users has in them. If Vitalik demonstrated extreme prejudice against ethereum's users, then the users would (probably) revolt, and new developers would be installed, but critically: Ethereum, like all blockchains, enables that in a way which doesn't involve the war, death, and bloodshed that overthrowing governments typically requires.
Miners want to have their cake and eat it too. They don't give a shit about Ethereum's users. They want a high ETH token price, wholly and totally supported by Ethereum's users, but without this RFC, which both the developers and most users support. They could fork, give the middle finger to the users, and their secondary TRASH-ETH blockchain would be worth nothing, because it doesn't have users, but at least they'd have proof of work. That's why they'll lose; not because the developers are on the other side, but because the users have put their faith in the developers, not the miners. And that's a very healthy position for ethereum to be in right now.
So if developers released a "jubilee" version of the software that took all ETH away from addresses that hadn't spent anything in 5 years, and distributed it evenly across all Ethereum addresses less 2 years old (which one might imagine would be a boon to a large number of users), would that be sufficient to upgrade the network?
Asking because one huge advantage I see in Bitcoin's upgrade procedure is that developers alone can't change the monetary policy -- i.e. developers can't just bribe users to screw over investors. I'm curious why the "All Core Devs call dictates software releases" upgrade process is considered an acceptable alternative?
> So is Ethereum not going to PoS if miners say no?
Correct
> Every soft fork was voted on by miners. Developers provide the code, but it only activates with miner consent.
Again, it's the same process with Ethereum.
Not sure if this is just a misunderstanding or if you're reading something that says this isn't the case, but if it's the latter then I suggest taking a good hard look at continuing to use this source for information.
Bear with me here, but I strongly suspect that this is not the case. Because PoS doesn't need miners, it seems the system can transition to PoS at any time and there's nothing miners can do to stop it. So unless the miners also happen to control over 50% of the staked ETH supply, miners don't have a say at all.
EDIT: Don't get me wrong -- I wish Ethereum could only upgrade with overwhelming miner consent. It would check the power of developers to alter the monetary policy as capriciously as they have done so far.
This is actually a current issue that's being discussed because the transition fully relies on the miners to make hand off the transition because of the contention with moving to PoS. One possibility is that miners will fork the chain, although that's not necessarily a huge concern because the community will follow the PoS chain. Another possibility, and I'm a bit fuzzy on the details, but it has to do with them re-mining the same block over and over so the transition block never happens (or something like that).
So is Ethereum not going to PoS if miners say no?
> Blockstream does the same, it's literally no different.
Every soft fork was voted on by miners. Developers provide the code, but it only activates with miner consent.