I think your point is dead wrong; I remember parity, and it was boring. How many really good western conference playoff series played at high levels can you remember from the 80s, when the whole conference aside from LA seemed to be bunched up around the .500 mark? About the only one I can think of was LA-Dallas in 88. Where you had great teams in the East, there were incredible series all over, like Boston-Philly in 81, Boston-Philly in 82, Boston-Detroit in 87, Boston-Atlanta in 88, and Chicago-Detroit in 89. You're just bringing conjecture, but I'm bringing real examples of what parity was like.