this is how I see it
70s: good genetics + AAS, knowledge on training was train hard, diet knowledge was protein build muscle, carb give energy, fats bad if there oil or from anaimal
physiques had generally good legs, thin waist, dominant chest/arms/shoulders, conditioning was good but had a fuller appearance
80s: saw intro of some GH, comman trenbolone usage and strong fat burners: physiques were leaner then the 70s, saw a mix of bodybuilders shapes, physiques though did become harder, leaner and fuller/drier, most guys weren't much bigger then 70s bodybuilders but were in much better condition, saw big improvements in leg development areas
90s: intro of GH+insulin: saw dorian first master it, physiques jus became on average larger versions of what we saw in the 80s, waists became a little thicker but the overall body grew enough to compensate for it and the huge v shape was still maintained, so we saw freaks like flex, shawn ray, kevin levrone, lee priest, Nasser, Ronnie, dillet, matarrazo, jay, etc, also saw guys coming in a lot drier in this era more then likely due to diuretic abuse which was known to become popular then, saw early signs of insulin guts (dorian)
late 90s: guys were bigger but Ronnie was changing the game, synthol use was becoming common with a lot of genetic weaknesses not being present on the Olympia circuit anymore
2000s: insulin gut become very common, guys were getting a lot bigger and the average size of most guys was freakin huge, conditioning started becoming an issue with guys either hitting/missing the mark with either coming in shape or soft and bloated, you could guess this was the era large doses of slin and GH protocols weren't know well enough for guys to come in consistant, synthol abuse almost a must for every pro
ooooo and in the early 2000s scientists finally agreed that AAS increase athletic performance