Does he need to average 2 blocks? We all want him to go out and get 5 blocks a game, but do we really want Davis selling out for every single upfake? DeAndre Jordan tried to block every shot and he winds up being made a fool of. Cuz that's all people are going to do. Show the ball and try to draw the foul or drive around him. And guarding people like Diaw who are gonna sit near the 3pt arc? Won't get a ton of rebounds either.
Blocking shots isn't the only way to play defense.
Davis will get his blocks when he plays center. He's a great help defender near the rim, but that's taken away when he's out near the 3 point line. He was a shot blocking machine even in the Olympics so it's not like it's the talent level preventing the blocks. At PF though, he's playing farther away from the rim than he did at Kentucky as most PFs have range on their shots.
I still think he'll primarily be the center on this team in a couple years though. Better for him to take on the physicality of PFs than Cs as he's still putting on weight righ tnow.