When they were both playing I don't remember for one instant thinking that Wade was as good a player as Pierce. I always thought Wade was the luckiest player in the NBA because first Shaq and then Lebron voluntarily joined his team.
Even if their career stats are comparable, as others have noted. I can only imagine what Pierce's numbers would have looked like if he spent a large portion of his career without facing the double and triple teaming that was used against him every night.
A lot of revisionist history floating around during Wade's retirement year.