I agree. I had a desiccant that when you heat it in the oven it can be used again. (it would change color) I also had a airtight jar made for it so it wouldn't touch the item you want to dry. I love chemistry. But no expert. I had a Gilbert...
Rice from a bag on a supermarket shelf is not "very dry." It's close to equilibrium with the ambient air. Chemical desiccants have a much greater capacity to absorb water than rice and they can be regenerated.
If someone was really interested...
interesting as I have a chemistry background. Anything very dry that can take on water will absorb water to some degree and it's best to take the drone apart instead obviously then go from there.