I would say the price is the determining factor in the example of the GTX 1060:
(sorted by price, GTX 1060 6GB, sold as new by Newegg)
I can hardly believe the GTX 1060 is responsible for everyone suddenly wanting smaller cards when all the manufacturers have been doing is selling increasingly larger cards. But in the end, this is not a bad thing: more people using smaller cards means manufacturers will focus on smaller cards meaning more SFF GPUs for us !
Maybe Newegg had a good deal, maybe they've bundled it, many factors can skew that view with the amount of reviews being the main factor.
Yes. But it also shows that people don't care for oversized dual fans with outrageous board height and most would rather have the smaller cards. Dual fan versions are only $10 usually like MSI Armor editions, or in your example no price premium vs the EVGA version. It's a mixture of lower cost, lack of 8pin requirements and a smaller form factor.
The 470 and 480 release focus exclusively on oversized boards and fans with premium features like back plate, LED, and swappable fans. There is a market for a budget small form factor 470/480 despite what most people say. Everyone keeps giving the spill how there's no market for smaller cards but every evidence points to the opposite. For example the zotac mini 1060 has one of the worst coolers but still sells well despite not being that much cheaper.
Also people disregard prebuilt upgraders. Despite being a decent demand. Those guys want the best bang for buck and it is ridiculous that there's no small 470 for them which is best position to take advantage of that market.