Zingis is more or less still as efficient a shooter as he was in New York. A little less efficient from mid-range, much more efficient at the rim, shooting the same from 3. And he's creating for himself a little less, but that's largely due to Luka getting him open looks inside so frequently-- with the Knicks, 64% of his 2s were assisted and nearly 99% of his 3s were assisted, while in Dallas, 72% of his 2s are assisted and 97% of his 3s are assisted. So outside of playing at the rim more and shooting off the bounce in the mid-range a little less, not much has changed in terms of his relative offensive efficiency imo, even without the speed, just because he can straight up shoot over most people. If anything, Luka's made his life a little easier getting open shots, so they probably wish his 3P% off the catch (38%) was higher.

The problem isn't his offense as much as it is his defense, that's where the lack of speed is really glaring. He's not even rotating over to protect the rim as efficiently. The Mavs don't need Knicks Zingis on offense, but they badly needed Knicks Zingis on defense-- namely, a guy who is okay for his size on switches and is a very competent rim protector. Now, he's appalling on defense, a total liability to the point where I don't know what they can do with him. They need his 20 points a game, but he also has the worst defensive on-off numbers of any of their major contributors by a lot, to the point the Mavs were a notably better team by the numbers when he wasn't on the floor. (Meanwhile, his last two years on the Knicks, they were a much *worse* defensive unit without Porzingis on the floor by the numbers.)

So really, they don't need much from Zingis on offense beyond what they have-- and the things they need offensively from him wouldn't even really be helped by added mobility. He just needs to shoot off the catch at a slightly higher percentage to help spread the floor. But man, they could *really* use his Knicks mobility on the defensive end. So the injuries affected that, for sure.

But going back to the original point, even if Zingis was a Knicks-level competent defender, they paid him the same amount that, like, Minnesota paid Karl Anthony-Towns and Phoenix paid Devin Booker. Denver paid less for Jamal Murray, Boston paid less for Jaylen Brown. If you're paying that for Zingis, you have to think he's the second best player on a title contender at minimum... and they paid him that *after* he sat out for a year due to ACL surgery. That is... a *lot* of faith.