This is essentially a re-post of a comment I made here, which I am opting to put out there because it seems prudent to do so.
It took me over a year to understand what made PoW and PoS truly different from one another. It feels at first like it is simply PoW depends on power, PoS on coins. But that is the wrong way to think of it, as it truly comes down to trust and network oversight.
First, this episode of the Bitcoin Dad Pod is what finally made it click for me, I would highly recommend giving it a listen.
TLDR: Power vs coins is the wrong way to frame it. In PoW you trust the constraints of thermodynamics and probability. In PoS you trust the honor of those with the money.
Full Explaination: Essentially, the idea of PoW being who has more power and PoS being who has more coins is an oversimplification of how it functions, although obviously no one blames you for the confusion, as it's an easy mistake. Although in PoW you can 51% with enough ASICs and in PoS you can 51% with enough coins, the true difference exists in what happens while each protocol is operating normally, ie, when no 51% attack is being preformed.
In PoW we achieve decentralization by requiring every miner to put a hash with a certain number of zeros on each block. This is a requirement enforced by the nodes, ensuring that a certain amount of work must be put in to count a block. If a block does not meet these requirements then the nodes will reject it and wait for another miner to broadcast a block. The network gives oversight and enforces strict standards.
In PoS, the nodes don't have any such requirement. All that the network asks of stakers is that they lock up a certain amount of their coins and continue to produce blocks when it is their turn. Essentially, you trust that those with the money to stake coins have an incentive to not overtake the network, censor transactions, etc. There exists little to no network oversight. If the coins are staked, everyone runs with it.
Thus, we have a fundamental disconnect. PoW has distinct requirements imposed by the nodes to ensure decentralization and non-censorship, while PoS nodes set no requirements. Granted, you coins can get slashed under PoS, but that is only in the case where either your staking node goes offline for too long, or if you try to send out two blocks at the same time. Neither of those ensure decentralization in the same manner as PoW, as censoring transactions and 51% are not effectively prevented by these methods.
PoW vs PoS is a very complex topic though, and I would encourage you to research it more. But at the end of the day, they are dramatically different protocols, making it so that "PoS is PoW but coins instead of power" is somewhat of a mischaracterization.
This post in meme form:
Everybody agrees with that. BUT:
  1. PoS works nonetheless. Some PoS blockchains have been working well for years, and so does the "new" Ethereum. In this whole debate, it's always "bad things could happen". But sometimes they don't — and things just work.
  2. Most people on earth don't give a dam about this debate. They don't know what is PoS/PoW, never had, never will, for the same reason that most of them don't know how money works, how Visa/Mastercard networks work, or what Central banks do. People just care about their own needs and when it comes to managing their money, they are only after convenience, price (low fees), speed, and security. If a solution (any coin, any blockchain, any "proof of") brings them that, they will go for it.
So constantly using this PoW argument to advocate Bitcoin is useless. It's geek and will not get us anywhere in the real world. Even if, yes, PoW is better, from a security point of view.
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an unfortunate truth. in the future, the average person will probably be using bitcoin without even knowing it
i think most people that begin falling down the rabbit hole do naturally ask this question though so it's still an important question to be able to answer for yourself and those with questions. passing this education onto the next person is how we get more bitcoiners
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Yup. Unfortunately, most people won't care. I think that's why Bitcoin is probably going to win through lighting and store of value, and PoW will just be a thing in the background like you are describing.
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It isn't pointless at all. You are correct about the masses but talking about this stuff isn't for the masses its for the select, the remnant. The thing is, you never know who will read/hear this info so don't underestimate the power of explaining the "geek" things. The people that truly want to learn and understand are often influential and leaders.
On the point of "bad things could happen". Do you really think PoS can withstand state attacks? The ETH validators are already bragging about OFAC compliance... In a perfect world this stuff would not matter, but we don't live in this magical world. Bitcoin's approach to censorship resistance is one of the main things that got me. Yes these same attacks can be done to bitcoin but it is much harder to execute.
A common mistake people make is watering down things. I find that those that don't care about the security of the network and censorship resistance come from places of privilege like the the wealthy western world. Often they seem to have a Pollyanna view of the state. Bitcoin is a real threat to tyranny and many will try to stop it. We can't kid ourselves.
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PoS works UNTIL IT DOESN'T. And it has a tendency to get corrupted and centralized over time. So that's a very short-term argument.
People don't care about this UNTIL THEY DO (their first rugpull). And PoS ALWAYS EVENTUALLY leads to the rugpull. Humans are gonna human.
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PoW provides stronger assurances by removing the humans from the equation.
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Proof of stake is like corporate democracy, control of the company, and control of goes in accordance with your stake, or, stock, as they call them... If you don't call a corporation and it's board decentralised then neither is any proof of stake network.
This is also why the tokens are securities. The biggest stakeholders can abscond with everything.
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