Discussion Question: Is their a lack of parity in the NBA?

Now in some fairness there are mitigating factors in some of these situations (Derek Rose’s injury for example) but of the eight playoff series, one (the Thunder over the reigning champion Mavericks) is already over, another (Spurs over the Jazz) is at 3-0, and five others are at 3-1. Now there is a chance the Grizzlies could even up the series and at least show a pulse, but that is pretty bad to have essentially series out of reach after 4 games. And it bears to mind the question as to whether or not there is parity in the NBA, and if perhaps they should reduce the number of playoff teams.