I dont really understand the context of the statement, but I would imagine they are saying its like pulling money out of the economy, but thats not true, its like trading two currencies.
Maybe they are saying this in reference to what Keynes said once about burying money in order to combat inflation, however the only reason that could be considered as such at the moment is because bitcoin is not being used as a currency and most of the people that invest in it do not withdraw their money immediately, but as soon as that changes bitcoin is going to be like any other currency.