For most skiers, highly wind resistant is actually the sweet spot. It blocks the vast majority of wind but allows just enough air permeability that you won't feel clammy or stuffy when you're working hard on the slopes. You might notice a slight breeze at very high speeds, but for typical resort skiing, the protection is more than adequate.
The real advantage over fully windproof options is breathability. If you've ever had your goggles fog up or felt moisture trapped against your face, that's often because a fully sealed balaclava can't let vapor escape. Highly wind resistant designs strike a better balance—they keep you comfortable on cold chairlift rides while still managing moisture during active skiing.
Go with highly wind resistant if you ski a mix of conditions and speeds, especially at resorts with both exposed and sheltered terrain. Reserve fully windproof for the most extreme wind chill days or if you primarily ride wide-open, exposed lifts where every bit of wind block matters.