PoS coins use the number of coins held as the basis for their signalling system. Since coins have an exchange rate, they obviously do not fulfill the criteria of having no value, either practical or intellectual. Thus PoS is not an viable mechanism for honest signalling.
Aren't you confusing the stake (which can be reused to provide signaling for many transactions over time) with the coins (which can only be used once)?
The stake is worthless as far as I can tell. Stake is just showing someone what you own, not actually giving it to them. Would someone pay me just because I show them that I have a lot of money in my wallet? I can show what's in there a million times without losing a cent.
Actually this is a compelling reason for PoS, it's a physiological phenomenon, I have power therefore I demand you concede.
I guess it's not an elegant power phenomenon.