One thing Square could've done was try to promote DQ more in the West when DBZ became a thing. They could've tried to ride the coattails of that, considering it's the same artists working on both, to draw some attention.

Also, they mention FFVII as the source of nostalgia for FF fans, but I would argue that the SNES games were even more so. The 16-bit era was when RPGs started making waves in the west. You had FF as #1 and maybe Phantasy Star as #2. Then you had Chrono Trigger, which just blew up. The Super Famicom version of DQ weren't even released in NA until many years later.