Last year, the Oakland Raiders took OLB Khalil Mack, the draft’s best player, with the fifth overall pick in the draft. Everyone then expected Mack to get 16 sacks last year but it didn’t happen and it was through no fault of his. According to Pro Football Focus, he was the best in the NFL at what he did and that was play 4-3 OLB.
The Raiders blitzed less than any team in the NFL last year so Mack only rushed the passer on third down. Teams throw on first and second down a lot these days, especially when the defense’s best pass-rusher only rushes on third down.