I wonder whether this was all a ruse to upsell consumers to 16GB models with greater margins. The $50 price difference is a bit steep for modules that shouldn't cost that much. Spitting out a few numbers...
If AMD's, for example, 'ideal' margins were selling the 9060XT die at $325 with 16GB of VRAM, they offer an 8GB version for $300 knowing no one will buy them and upsell consumers to a product that should cost $325 but is $350. AMD pockets the extra $25.