Dual-lens goggles without anti-fog coating rely on the thermal barrier between the two lens layers to reduce fogging. This double-pane construction creates an insulating air pocket that helps, but it's the most basic level of fog protection available.
These goggles work fine if you're sticking to resort skiing on dry, cold days and you're not working up too much of a sweat. They're a reasonable choice for casual riders who ski a few times a season in favorable conditions.
However, they struggle in humid or wet weather, and they'll likely fog up if you're hiking for turns, skiing hard on warm spring days, or caught in a storm. If you ski regularly or venture into variable conditions, spending a bit more for anti-fog coating is worth it. Just remember—never wipe the inside of any goggle lens, coated or not, as it damages the surface and makes fogging worse.