Was just thinking last night, why are higher capacities higher prices?

Surely pretty much everything is materially the same between a 1TB and 2TB capacity, where does the extra cost come in?

I used to think this with HDDs but I guess there were drives with higher numbers of platters or higher densities or whatever, but these are just silicon right?

2X as much flash memory is needed for 2X the storage. That's either more chips, or chips with more stacked layers.

And even if it's not more layers, I'd bet that a chip with higher density circuits requires more expensive fabrication and QA systems. And I'll bet the yield is lower too (number of good chips you get out of a manufactured batch).