the conservative coffee fantasy is rooted in the association of coffee with ruggedness

I agree with this, this is most of it. Another part is the general suspicion of outsiders and external ideas. To them, it’s just rebranded coffee, coffee being a famously cheap thing. They think that a latte is just an overpriced drip coffee, the same way many users here are suspicious of Apple selling overpriced computers. The more breathlessly you explain espresso to them, the more they think you are blowing smoke up their ass.