If a money supply remains constant while the economy grows, eventually the money supply becomes inadequate to facilitate trade throughout the entire economy. Consequences vary, but all are disruptive.
False. So long as there are enough divisible units to cover the small transactions, it matters not how much money is in a system. Bitcoin is infinitely divisible, and a world in which a car costs one trillionth of a bitcoin is no different functionally than a world in which it costs 1,000 bitcoin. Prices adjust to the money supply, and there is no reason to tamper with it or inflate it merely to hold prices constant.