I dunno ...
I dont see core of this question in Lack, or Need of "sexy" (Let's put aside that even the very definition of this word differs from person to person) armor ...

But in fact that designers usualy focus on just only option, and let the other go. :-/
Therefore one group is allways forced to submit to the other. :-/

If there will be "some"(!) usable types of both, what is the harm?

I liked original spellcasting system more ... frown

Anyway ... i cast Eldritch Blast!