Imho PoS coins are for the lazy rich investors. They can make a stash of the coin and they get a stable profit from PoS.
I can't say I studied all the PoS coins deeply, buy my overall impression is that even in the good days of crypto market, the PoS coins' price starts to decline pretty early exactly because the "investors" continuously trying to sell their PoS profits.
What kind of PoS I prefer? The LPoS. It allows me to PoS without keeping my wallet running all the time, it allows smaller investors to also have some gains. It has downsides too, from not so wide decentralization to the need to somewhat trust a 3rd party to send you the income in a fair way.
Ya i do agree investors do sell off the pos profits in order to roi on their masternode and get that risk off the table, but I think miners do the same, They sell the coins they mine to roi on hardware.
That's why I try to pick a quality pos or masternode that has a very low emission rate. Less than 7 percent for me, the lower the better. Anything higher will just force people to sell off their pos coins at a high volume rate if your percent emission is too high.