I really don't understand why you want to argue about this. I said it is a silly idea that I just found amusing, and here are some reasons why the teams involved
MIGHT
want to do it. Now you want to say that you disagree with these reasons. Bully for you. It's not like this proposal would ever happen anyway.
(Edit: I just went back and saw that once I did write "would," instead of "might." I apologize for the confusion. Of course I meant "might.")
However, there is no team that is quite as dependent on open-court play as Jason Kidd's team. This is true no matter what team he is on. So Mutombo is a worse fit on the Nets than any other team in the league. If New Jersey exits the playoffs early, they will consider trading Mutombo. This will also be true if Kidd leaves and they have to rebuild the team all over again.
The Suns' offense is much more of a halfcourt offense. If you watch the games, you'll see that they don't run anywhere near as much as they did when Kidd was in Phoenix. The reason they don't use Tsakalidis is not, in my opinon, because he doesn't score -- it's because he is slow and unaware defensively. Mutombo is a much better defender than Tsakalidis. I think that, in the fantasy scenario where the Suns had Mutombo, they would use him.
Of course he is grotesquely overpaid and there are questions about his health. I've never debated that.