I didn't see anything in that article supporting the claim that PoS chains "are all highly centralized".

So according to you a protocol that prioritizes nodes with higher holdings of the crypto currency is somehow decentralized?

What difference does it make if the block-generating capital is ASICs or cryptocurrency? The distinction is completely orthogonal to decentralization.

Then don't make that distinction? I originally wasn't.

Point is, whether it is a huge farm of ASICs or PoS holdings, it still leads to centralization.

The original comment asking for a source was quoting an assertion that Proof of Stake blockchains, as opposed to Proof of Work ones, "are all highly centralized".

So given the context, I was implicitly asking for what distinguishes Proof of Stake from Proof of Work to make the former centralized where the latter is not.