The article calls out that there’s an unaccounted for bias in the reality that the Jazz will almost certainly trade/sit guys and develop youth though. That could easily account for the discrepancy
Even with a very conservative minutes projection for the vets, we're at 35-38 wins. There's always a margin for error with these models, but the reality is that it's going to be hard to get down to 20 wins with the amount of real, NBA caliber players we have.