A helmet without padding can protect against low energy penetrating impacts; think BBs or similar. They do this by spreading the impact point out over the entir

A helmet without padding can protect against low energy penetrating impacts; think BBs or similar. They do this by spreading the impact point out over the entire head; preventing penetration or fracture. But for pure G forces, you’re right. A helmet with no padding is effectively similar to not having a helmet at all.