Why is anybody trusting a word that JD Power and Associates says?
I do hear better things about Hyundai and Kia these days, but a mechanic friend once said, I think about Kia, "Yeah, they're great for 100k miles, but then everything falls apart." That's a broad generalization, but it's important to realize that reliability comes in many forms. I haven't seen a 90s Ford Contour in 10 or 15 years, not that I have eagle eyes for the makes and models of cars on the road. There's also a difference between a car that lasts a long time and a car that's worth taking care of for a long time. If the engine and transmission are known for being unstoppable beasts, people are more willing to pay for other repairs, for example. The real problem is when you have poorly engineered designs which cause parts to fail prematurely.
And the challenge is, just because a company was reliable in the past doesn't mean they are today. (Sometimes companies develop an ego and think they can get away with anything based on their reputation) It varies by model, by year, by parts. The 2007 4-cylinder Camry is known for burning oil because of the piston rings that were put in it. However, it's still a 2AZ-FE engine, which was otherwise super reliable before the 6th gen, if I understand correctly.
I think Toyota had a car that was basically made by Subaru? And that a Toyota engine or transmission was actually used in a Pontiac? [As in, Pontiac paid Toyota for it] These things make a difference. I'd stay away from fringe models, too. Just because a brand known for reliable produces it, doesn't mean it's a reliable model!
Frankly, this is one of several reasons I shy away from new cars. Sometimes you can plan to buy a model that is later in its own series, with the assumption that the issues have been worked out by then, but aforementioned mechanic friend says this isn't always the case, as sometimes the "fixes" end up being worse. Nonetheless, I'd never trust a first-in-series model, or brand new technology (I hear some early CVT transmissions sometimes didn't last 60k miles).
I bet Scotty Kilmer has weighed in on Kias and Hyundais....