Don’t we also have to take into account the volume of passing situations now compared to then? I mean, 30 passes in a game during Manley’s era was a lot. Today it’s probably below average. More passing downs, more opportunity for sacks.
Yeah. This. It is really hard to compare eras in the NFL with all the changes to rules. Unlike baseball where maintaining tradition seems to be important, sometimes to the point of being a detriment to the game, the NFL seems to have no sacred cows. If a change to the rules will make the game more exciting for the fans, then, by all means, let's do the thing. Player safety seems to be the only exception to that but even that has been driven by money, either in the form of trying to duck lawsuits or as part of a larger design to protect the investments made by teams in the QB position.
In the end, it is probably good for the game in terms of fan engagement, both in terms of modern-day excitement and in terms of fan discussions just like this. If the comparison were easy, I doubt we would spend as much time talking about Manley vs Kerrigan and where they rank in team history.