Goes with my general impression that these days you're often better off with high-end "regular" brands than going entry-level in premium brands. Example in case, from the awful Audi website, I get that one needs to climb up to 42k$ to get a rear-view camera in the A3 (base price: 31k$).
What the Santa Fe is missing over the MDX is the prestige nameplate and whatever that comes with or means to you personally.
Is that a comparison between both in the metal, or based on spec sheets?
I find that with the "prestige nameplate", you often get little niceties that are not listed on media pamphlets. For example, my parents' RX and my girlfriend's Forester both have automatic climate control. Are they equal? Objectively, by no means whatsoever. The Subaru will blow air at you immediately, even if the car is cold. The Lexus? It won't blow any air until it's warm (in the winter, at least - AC compressors are pretty quick!).
When you open the glovebox in both the MDX and the Santa Fe, do they 'feel' the same? Do all buttons have similar feeling? What of the headlights? The MDX has LEDs, whereas the Santa Fe has Halogens (or in the loaded case, Bi-Xenons).
Are the AWD systems equivalent? SH-AWD vs Haldex decoupling? If I understand correctly, SH-AWD will help with performance on dry pavement, whereas the Santa Fe is a slip n' grip, predominantly FWD (and can, as mentioned, decouple the rear axle under light loads once already at speed to save fuel).
I can go out and buy a Kia Forte with heated rear seats, a feature that was once found only in $$$ Cadillacs. Does that mean that the Cadillac is now overpriced?
I don't view the build quality, nor the amount of 'little things' (i.e. features) to be equivalent here. Is it worth $20,000? That's debatable - I would argue based on resale value alone that it is. However, I do understand the point being made here...Hyundai has made a very, very good car here that is well-priced, even if it is a lot of money for what appears to be the value-oriented Korean-branded 'lesser' vehicle. In that respect, I agree...but I do not agree with comments like these:
Remind me again why the MDX costs $20,000 more than the Santa Fe XL?