The reduction or elimination of lactose in ice cream and other frozen dairy desserts goes back to well before the simple declaration(s) of “low carb” in the early 2000s. Lactose removal was, and is, many times related to its contribution to total carbohydrate, total sugars, calories, and glycemic index, not to mention market positioning related to prevalence of lactose intolerance.
Only about 10-12% of the U.S. population is truly “lactose intolerant.” Lactose intolerance is just that — an intolerance due to the lack of ability of certain individuals to make the lactase enzyme. Lactose is not a true food allergen.