The short answer is that Les Gets removes a lot of the daily friction that comes with skiing alongside young children. The village centre is compact enough to walk between accommodation, ski school and the nursery slopes without needing a car or a shuttle. Beginner terrain sits close to the centre rather than requiring a lift ride to reach it, which matters when a three-year-old needs a nap before lunch and no one wants to be stuck at altitude when that happens.
None of this means skiing with young children is effortless anywhere — it isn't. But the practical layout of Les Gets tends to reduce the number of things that can go wrong in a single day.