How are the functions of money being a store of value and means of exchange mutually exclusive?
To be a good store of value money needs to be appreciating (the more the better). Conversely, to be a good means of exchange money should be depreciating at a slow (and low) but constant rate. The former contributes to hoarding while the latter to spending. Hoarding and spending don't live well together and are, in fact, mutually exclusive. In other words, you can't hoard and spend the same (amount of) money at the same time...
I don't understand what you mean here. To be a good store of value, money only needs to be a stable store of value. When you say it needs to be "appreciating," do you mean appreciating in value- as in a deflationary currency (less in circulation over time)? That wouldn't be a stable store of value. Appreciating value isn't stable, and a stable currency is superior to a deflationary currency because as you point out, deflationary currencies would incentivize hoarding and harm economic activity. On the flip side of your point, a currency doesn't need to depreciate in value (be inflationary) to be a good means of exchange. The only requirement to be a means of exchange is wide availability. A stable value, widely accepted currency would satisfy both the store of value function and the means of exchange function of money. These two aspects don't have to be, and most commonly are not, mutually exclusive at all.
