Were you there? I trained at the same gyms they did and before
depends on what you mean by where and when.
in the 80's we had lee haney, there's footage of his training on youtube, he went by the 'stimulate not annihilate'.
in the early 90's we had dorian yates, he trained hard, and the whole purpose of his video was to show that he trained hard, now if everybody was training hard, that video would never have been made.
in the late 90's early 00's we had ronnie coleman, again, whole point of video - showing how hard he trains.
this tells us that training hard was THE EXCEPTION not the rule since the 80's and onwards.
to wonder in 2018 why bodybuilders stopped training hard, something that they havent been doing for at least 30+ years seems quite strange, its not like it''s a new phenomena.