The difference between Bayless and Smith is that Bayless is somebody who knows sports and plays a dumb commentator as a schtick.
Smith is a horribly dumb commentator, period.  He's not acting.  
Then there's his schtick which makes him look like a bigger idiot.
Iverson I can understand wanting to be on Smith's set.  When Iverson and Smith are together, captioning should be mandatory.
Pierce??  Why would Paul waste his time?