Quantity of bitcoins is decreasing due to some bitcoin holders are hiding it and waiting for the price increase of bitcoin.
There should be some kind of law that prohibits the hoarding of bitcoin. This is dangerous to economic balance!
I guess there is but I'm not sure about that I forgot if there is a particular law about that.
Yes, that is dangerous to the economic balance as other bitcoin wallet address with bitcoins forgets their private key and it will be lost forever.