The problem isn't the external drive cost, it's persuading users to buy an addon when it isn't Nintendo branded and there are way too many options. For example an average customer might accidentally buy an internal drive.
I don't think HDD size in the console was the motivation for the low capacity. All hard drives are pretty small now, and you can trade density for cost/performance. I think it was the cost, because after the absurd Gamepad price they didn't want to lose more money on something not essential.







