It depends on how the training is done. In the TKD place I used to go to (over a decade ago), we practiced full contact with punches to the face. So in that scenario, the lack of face cover wasn't quite an issue. If it was an Olympic or WTF style TKD place, then that would have been a no-no and it wouldn't exist. To risk sounding cliche', it really comes down to the practitioner.
Generally speaking, it's not the "style" or the techniques between the two that makes a difference. Rather, it's the way that training is done. Once you introduce live sparring situations, where techniques are continued past the initial set within a kata/poom, and all the chaos that comes along with that a person will learn how to fight and defend themselves to some level of confidence one way or the other. That would happen with TKD or any given style. Given that the majority of MT practitioners train with that in mind, and the majority of TKD practitioners don't. I would give the edge to the MT practitioner more often than not.
It doesn't matter if you agree or disagree
... As long as I don't bore you and I spark a moment of thought, my goal is achieved
Queng leon queng tigre ecu tacacut, queca pa? - Pampangan Mandarigma Motto