The monopoly profit maximizing price for a card is going to depend on the precise shape of the demand curve for each individual card; It may be $10 it may be $50; the fact that they could crash the price whenever they want does not mean it is in their interests to do so.
So my thinking is that if they control supply (they do of course), they control demand, and that there is no “per-card” demand curve. If a card is reprinted and drops from $100 to $50, they can reprint until it’s $10
I think you do not understand what a demand curve is and should look up some econ 101.
The demand curve is how many of a given card customers (in aggregate) would buy at a given price.
Wizards could reprint any card into the ground if they wanted to (which would be far below $10), but that would likely not be the strategy that generated them the most profit, and there's no actual reason to think $10 is the price point that would do so either.
Asking someone to look up Econ 101 isn't necessary to make your point.. You probably knew what I meant. You probably knew that my point is they control the supply, so they control the price- the equilibrium price if you like.
