Or the reality that there are now chips available that offer the required and actually intended sizes for all SKUs.
We know Nvidia rushed Ampere to market by now, it echoes in everything, and that includes VRAM capacities. Your idea of 'uneducated buyer' buying into high VRAM caps is an idea of the ultra low end/budget class of GPUs where we also saw said capacities to turn out being DDR instead of GDDR memory even. Its old news, those guys are buying laptops, tablets or smartphones and have been for a decade or more now.
Nvidia NEVER pushed the marketing button for any of its x50 > x60 and up cards like that, so I'm not sure where you're coming from. They always marketed the normal VRAM versions first and foremost, and the double cap ones were obviously meant for the (then also still normal) SLI solutions. Your frame does not fit on the current situation at all either, where is the 20GB 3080 if people are so eager to buy inflated capacities? Let's remember here what you're defending: 10GB is enough but 'because marketing' double cap is on offer. If it'd sell that well, why wasn't it sold first - especially knowing a 16GB Radeon card is also available?
EVEN the odd one out of late, the 1060 was marketed first and foremost as a 6GB card, which
also had a budget-ey 3GB cut down version. Today, the 3GB one is sinking fast and cheap becomes expensive sooner rather than later. After all, you'll be looking to upgrade that by now, it won't do much anymore without heavily cutting back on IQ. Ironically around the same time a 970 is hardly ever recommended despite having "4"GB
NVIDIA today added the NVIDIA® GeForce® GTX 1060 to its Pascal™ family of gaming GPUs, complementing the GTX 1080 and 1070
nvidianews.nvidia.com
People are apparently just making shit up now to defend 10GB. Wow. As if it cannot occur that Huang made a timing decision that isn't the best design/balance decision for its GPUs going forward. No - that couldn't possibly be the truth, right? Surely he isn't in it for the money?
Here's some fun reading material
https://www.reddit.com/r/pcmasterrace/comments/kkl86c
All the ingredients are there - none of them speak of 10GB being a solid choice for anything other than pure necessity.
Ampere is rushed, baked on an inferior node, badly balanced, and not quite the value you'd want even with the competitive price tags. Its not bad... but it certainly isn't great. Let's stop deluding each other. 200% core power, but 120% VRAM compared to past gen same-tier examples, just face the numbers and draw the logical conclusion.