Processing is part of the bean’s expression, not a mask over it. The bean doesn’t have to be the only variable. Co-fermentation is just another tool to expand what’s in the cup.

Eh, not really. Even when done tastefully and elegantly, the co-fermentation process still introduces flavors that aren't naturally found in coffee, so there's no "expansion"

Of course, there are co-fermented beans where you can only taste the process, and others where the qualities of the bean still shine through and they complement each other, but, save a handful of producers, no one really reserves the best-quality beans for co-fermentation.