I think it has a bit to do with

GM pulled out of factory racing support during that time .

So that era heritage was lost with them

Ford was focused on the Mustang (rightly so)

And, Max-Wedge / Hemi Mopars were the baddest of the bad, then and now


And, what 572 said is true, you take a old B-body to the track, better like to talk to people cause they will wear you out with stories , etc