Like in all sports, there's an evolution in not just style of play, offensive and defensive schemes but in also the average height, weight and overall athleticism in the league. Players now on average are stronger, faster and more athletic than in the 90's and 80's. Yes there were exceptions, however the league adapts and GM's start drafting and conditioning players on the new model. When that doesnt' work anymore it evloves again. Just like in the 50's and 60's in comparison to the 80's is jarring, so is the comparison to the 2000's. Just watch old NBA classic games. Unfortunately you'll only see the greatest games, like playoffs with the best teams, skewing opinions and colouring an era with a positive results that are not accurate to begin with. Being physical only gets so far when you're chasing bigs that at one point would play in the paint, where now they are a threat throughout the set.