Not really out of date so much as it is resource heavy. The consensus is that POS only serves to make the rich richer. How do you explain to investors that a POS coin which just multiplies itself and requires little to no resources. Is worth as much or more than a POW which requires large amounts of resources to produce? In a POW atmosphere everyone is welcome to join in the fun, flip on their computer and generate support/value to the network. This enables so many more people to participate. Whereas a POS model tends to exclude many people who would otherwise participate. Unless we’re discussing straight up ponzi’s like EMB. Given that you need (x) amount to stake or set up a node. That could be a 10,000USD investment in itself. So you broaden greatly your level of participation with POW.
That’s not to say that if something where to happen, like with ETH. Where the drain of resources were so massive on the planet, the only responsible thing would be a POS model. Then I’m certain the boffins would adhere. We all want the same thing after all.