I have to imagine that "emergency use only" is the idea that the Development Bros have in mind for Cure VI, since the amount was reduced alongside Cure V rather than increased. Well, assuming they have ideas and minds and stuff.

These changes seem like a big win for every job involved. Red Mage and Scholar will have a substantial Cure in Cure IV and even Cure III will be workable. White Mage will more-or-less have three flavors of Cure V after these changes go live. Traditional Vanilla (V), a quirky Dark Chocolate with Toffee Bits (IV), and Sugar-Free Low-Fat Gooseberry Licorice that melted and refroze (VI).

Everybody's MP efficiency will go way up, and White Mage's MP efficiency on lower cures will be huge. It's hard to care that Cure VI is apparently intended to be mostly superfluous when, well, Cure VI is going to be mostly superfluous.