To me the logic behind Proof of Stake is more like "so much money is bet on the answer being correct, that we'll assume it is. If the majority is wrong then feel free to permanently leave this chain and start your own". I consider it to be a superior system to Proof of Work in nearly every way.
The problem with that is that you only know that 'so much money' is being bet because you know who owns the money. But you only know who owns the money because that same money was bet earlier by people that you know owned the money because the same money was bet earlier by...
It's completely circular. It's like the Bible trying to proof itself. With no anchor to the physical world, you can't actually ever know
It's not completely circular. For example in casper-ffg if you as a full node log in every 4 months starting from ethereum's genesis block (about 3 years ago), the chain of logic you outlined terminates at the genesis allocation and PoW rewards.
I'm not saying that requiring clients to log in every 4 months is a reasonable security assumption, just showing that hand-waving it as "completely circular" is incorrect. It's more nuanced than that.
How did the node get started in the first place though? Unless you were part of the genesis block yourself, you only believe the history at all because someone told you it was the right place to start.
In full PoS in the model I described you'd need social consensus to determine the allocations in the genesis block. In PoW you need social consensus on the genesis block as well - the PoW algorithm, the initial difficulty and block reward, the difficulty adjustment algorithm, the block reward schedule
Corporations is controlled by those who own the shares. 1 share 1 vote. But usually only a very very few individuals own majority of the shares. So they have all power what a "too big too fail corporation" can do.
With Ethereum PoS. It is dependent on ETH being distributed to many individuals. If only a few individuals own most of the ETH, then they will then have the power dictate what is the "truth" in the blockchain. Right now, ETH is very well distributed around the whole planet.
As you can see, one is oligarchic, the other is very democratic.
Ethereum is not a Corporation that is designed to make profits. It is non-profit, it's not even a company, it's simply a protocol implemented in Free Software.
Allow me to hyperbole this a bit. If we go back to 2008, this is like saying - "there is so much money bet on subprime loan being correct, that we'll assume it is". And it worked for sometime before it dint.
