We'd have more money plus a starting spot. I don't know what JaMychal Green's priorities are, but I do find it funny how often we conflate something not happening with the idea that it couldn't have happened.
I recall debates about how important Favors was despite only getting 23 minutes and not closing games. Green played 23 mpg last year.
I do think we are in need of a bigger body that can play the 4, defend, and hit the three. There will be matchups where we will need that. And, yes, times where we will have to close with that on the floor. Not often, but a lot more often than the Favors/Gobert tandem closed. We lost a lot of games last year where we could secure a defensive rebound. Aside from Gobert, we didn't have rebounders on the floor because Favors didn't close due to spacing issues. Green rebounds just as well as Favors, but connects on 40.3% from deep on just under 5 attempts per 36. He plays defense.
If we don't want to view him as that important of a piece because he won't close games, then fine. But realize the comparison is Exum, who isn't closing games, and is valuable as a hypothetical.