Thanks to Pro Football Reference, NFL.com, NFL Next Gen Stats and the nflFastR project for being awesome sources of data.
In 2020, the NFL set a record high in scoring, averaging 49.6 points per game (PPG). However, since that peak season, scoring has retreated each of the following 3 years, falling to 43.5 PPG, a mark lower than 2008.
That may not seem that remarkable, but prior to 2020, the largest scoring drop was -2.