The overall summary is:
- It was a mutually beneficial trade
- It's hard to say who won right now until we know what the Knicks do with the cap room they now have, how Porzingis recovers from his injury, and what he decides to do with his qualifying offer/next contract
- If you have to pick a winner right now, it's the Mavs
The reason you pick the Mavs as the winner right now is that they just made themselves immediately relevant as playoff contenders in the West and if Porzingis signs a multi-year deal instead of taking his qualifying offer this summer (unclear which he does) then they have multiple years with two legitimate stars. That's a big deal for a team that has not had any success signing stars in free agency and won't be bad enough to have a top 5 pick in the next few years.
However, there are a lot of uncertainties right now and it could also backfire for the Mavs. Porzingis has had a lot of injuries since coming into the league and 7'3" players often don't hold up well long term. It's possible that he's not the same player he was before the injury, but considering how much of his skill set relied on height and shooting ability I think he'll be just fine.
Also remember that Dennis Smith wanted out so they had to get rid of him to get something back.
On the Knicks side, Porzingis wanted out so they had to get something for him. It would have been difficult to get a real star given his recent health issues and the fact that he said he doesn't want to play for the Pelicans (so couldn't be in an Anthony Davis trade). Instead of trading him for just ok players that take up cap space they:
- Got picks
- Got rid of bad contracts (the expiring deals won't hurt them long-term)
- Cleared up cap space to take a run at big stars this summer
So again it was mutually beneficial but my immediate reaction was that the Mavs came out looking great in this one.