First: Ok, so. Let's imagine that there was a perfect sound money. One that couldn't be tinkered with, one that couldn't be debased. Would you still need to "encourage spending"? I definitely do not think that's a given. I'd even argue that the need to intervene in the economy by playing with the cost of money is a symptom of the current system.

Second: Yes. No one is denying that Bitcoin is volatile. If you pick any arbitrary period of time you can come up with whatever statistic you want. This is not sound argument IMO.