The NFL is a money-making machine and has focused on making sure that continues for years to come. Whether it is forrays into fantasy football, betting or making events out of things like the combine and draft, the league knows how to market and monetize almost everything it does.
For more than a decade one of the ways the NFL has worked to increase interest in the game is by increasing offensive production. Defense no longer wins championships in professional football. Rules have been instituted to free up receivers from physical play, especially over the middle, and quarterbacks are, mostly, protected like they are a glass sculpture in the pocket.
There have also been other subtle changes where the NFL seems to be emphasizing or deemphasizing things to the officials to push the game in a higher-scoring direction. According to some data, that includes less holding penalties which has correlated to a low sack rate:
