Apple Stops Selling Mac Mini With 256GB of Storage, Starting Price Rises to $799
If they were dropping the most expensive model, would you say that it's a price decrease?
It's as if all apartments were from now on being built only at x2 the size, while keeping previous per square ft/m price. Prices wouldn't change, but effectively they would increase because many couldn't afford them anymore, making the average price increase.
Similarly, if biggest apartments were stopped being built, it wouldn't affect the average price that much.
Lastly, for commodity hardware like this, those who care about prices are those who need to count every penny. You and I might not care because we wouldn't get the cheapest config. But those who don't have much money and thus always resort to buying the entry level stuff, for them it's a price increase.