It doesn't show that. All your article says is that neuron trigger the gylmphatic system to create waves. It doesn't establish that the waves actually remove

It doesn't show that. All your article says is that neuron trigger the gylmphatic system to create waves. It doesn't establish that the waves actually remove more waste product. It doesn't even actually establish that the waves cause more flow. They are simply a "plausible mechanism to explain the correlated flow".