These videos were produced in cooperation with the Australian Rett Association. This organization wouldn't be promoting a drug that it didn't believe provides therapeutic benefit, especially when Daybue is already available (despite its terrible symptoms). And there are more stories like this that remain unknown to the rest of the world, for now.
Blarcamesine isn't a miracle drug but it does provide benefit and should be approved. If and when it is, there will be demand. And who knows, maybe if taken early enough it will allow for normal speech development. If not, it's still better than taking nothing.