As far as TLOU2 goes, it was among the highest selling games in the U.S. last year (above Ghost of Tsushima, second highest selling exclusive behind Animal Crossing), and one of the highest rated games of the year in several European markets.
I think it's sold fine. Not as well as the first game, but any concern around its performance is presumably misplaced, and I would presume it has sold more than 10 million, since it was doing better than Ghost, and Ghost is at 8 million. My assumption for why Sony doesn't share updates on it, to be honest, probably have to do with the game having become a flashpoint of controversy for chuds, much like The Last Jedi or Captain Marvel.
I assume we will get an update around the HBO series getting a proper trailer/premier date announcement (at the very least, I expect we will get an updated sales total for the TLOU IP at the time, and we will be able to derive sales of Part 2 from that number, if nothing else).