Maybe more 35~38 averages since it kind of started once everyone welcomed the existence/higher usage of the 3 pt line during Steph’s ascension in 2014.
Averaging 40+ is fucking hard which correlates with your idea of 40 points being common place.
Only Wilt, Mike and Kobe (I think Harden did it) averaged 40 for a month. And they are the pinnacle of offense excellence.
But
Defenses and schemes always adjust to curtail new/exuberant offenses over time. So I kind of doubt it.