It's tempting to max out on warmth, but extreme-warmth base layers are overkill for most resort skiing above 0°F. They're built for sub-zero temperatures, ski patrol duties, or long periods of sitting still—situations where you're not generating much body heat. If you're actively skiing or riding, an extreme-warmth base layer will likely leave you sweating through your layers, which actually makes you colder when that sweat cools down.
The bigger issue is that expedition-weight fabric can feel restrictive and bulky under your other layers. Most skiers are better served by a moderate-warmth base layer paired with a mid-layer they can adjust as conditions change. It's much easier to zip open a jacket vent or shed a mid-layer than to cool down an overheating base layer against your skin.
Save extreme warmth for genuinely brutal cold days or if you know you run very cold and spend more time sitting on lifts than skiing down.