Most of what I think these people were referring to was the Asians'
tendency to copy things. And Hyundai's been good at copying other
products.
The 2.4L 4 cyl in the 2000 Sonata is a purely Mitsubishi design, with
Hyundai manufacturing under license from Mitsubishi. The transmission is
a similar deal with Mitsubishi. The 2.7L v6 appears very similar to some
Mitsubishi engines, but I don't believe it's Mitsubishi's design, per se.
As for the electronics, I believe the 2.4 used Mitsubishi while the 2.7
used Bosch. In either event, Hyundai did what's called reverse
engineering. They took a computer system that had already been designed
for fuel and transmission management and built the system around it, while
making the necessary changes to the software.
As for current vehicles, there's still some collaboration. Despite the
fact that Hyundai claimed their transmissions were all new for the 2006
Sonata, they were really (at least in my opinion) nothing more than
revisions of transmissions already in use. I questioned my instructor
about this point and received an answer something like the friction
material being on one side of each metal, instead of having a two-sided
friction disc between each two metals. Big deal. In my opinion, although
somewhat more refined, there aren't any wholesale changes in the
transmissions when compared to your 2000 Sonata.
The 2.4L 4 cylinder now in use was designed by GEMA (Global Engine
Manufacturing Alliance), a joint venture between Daimler-Chrysler,
Hyundai, and Mitsubishi. I've heard no indications that the 3.3 and 3.8
v6 have design anywhere except Hyundai, but that doesn't imply they're not
someone else's engine designs. When Hyundai first began using DOHC engines
in 1992, the claim was that they were "Hyundai" engines, when in fact they
were nothing more than Mitsubishi designs manufactured by Hyundai,
complete with the Mitsubishi design flaws/weaknesses.
I'd have to reread my course materials, but I believe Hyundai is moving
toward using Delphi as their electronics designer/manufacturer on all
their car lines. I've already seen on 2006 Sonatas-- this would also
apply to the Azera and Entourage-- components that now look like they came
off a GM product. This doesn't mean that Hyundai is using GM technology,
but is likely to mean that the system has again been reverse designed.
I.e., Hyundai took a computer system that had already been designed,
installed the necessary components (which look like GM components since
both use the same system), and made minor changes to the software.