Would you happen to have a link for that? It would certainly help, as they are currently around where I'd call the minimum necessary (likely) PPD. Every little improvement counts until they catch up to 4k monitors, where anything looks good.
I don't have time to dig in and grab the exact spot, but I'm pretty sure they didn't go into detail much beyond what I said. My guess is text rendering is as good as it can be with state of the art displays, from a software stack standpoint.