I think the current situation in topics around graphics cards shows the opposite, people buy from the vendor that has the best overall deal.
The fact that AMD 'fans' want to be blind to those deals in some of their aspects of it, is their problem. But price is not the only aspect for sure. Thing is, Nvidia ruled GPU for good reasons since Kepler. People bought stuff that simply just worked, and it took AMD until RDNA2 to turn things around. As with Ryzen, they'll need several solid generations of GPU before you really see a market shift. Reliability and building trust takes time. Consistency matters, its one of the same reasons Intel can keep hold of its share quite well for quite long. Marketing also helps, but if the product underneath is not up to expectations, that won't last, while with Nvidia it did last. I say did because the sentiment is definitely turning - despite AMD (still!) having a feature set disadvantage, which says a lot.