...Shadowfox would ever recoup costs on a mold for 32x
I guarantee there is a way that 32x, regular Genesis, EA Genesis, Master System and Famicom can ALL fit PERFECTLY in the same case. There has to be. I just don't know what it is. So nothing to recoup.
Even assuming you're right, and ignoring the logic sheep pointed out (I too would have preferred a multi case, but hey whatever)... you overlook the fact that he would in fact have to recoup the cost of a new mold one way or the other

The Genesis repro mold has been created, no more tinkering with it (other than maybe if he's anal replacing the cover), which means whether he did a straight 32x or a multi case, he'd be pouring (and paying for) another one.
But hey, pipe dream. I for one am interested in SCD/Saturn longboxes way more than I am in 32x cases. I can modify a few Genesis ones, or have a few leftover UGCs, or whatever. Will stick out way less than DVD cases alongside my existing longboxes.
But first he's gotta recoup his money on the NES/Genesis molds.