"You would figure if it were simple while costing them less, they would port over a high selling game quite easily, but that's not the case."
That person wrote "not possible", not "isn't simple".
How could you not know the difference?
"SE realized the potential in releasing FFXIII for 360 and PS3 because for both consoles it can remain similar while not losing out on quality (at least not noticeably)."
Flashy graphics don't give a game more quality. Good design does. That doesn't magically not work on the Wii.
What the Wii does is not compromise the quality. It prevents the layers of razzle dazzle that hides weak design.
For example, I dare say that was the real problem with Chop Till You Drop (a game I like). It wasn't the Wii. It was that the original game was flawed to begin with, and the linear game flow didn't fix that (but the haters "somehow" forgot about those flaws because that would admit it was the developers' fault if a game didn't work, not the system). Contrast with Modern Warfare, which only lost DLC and local multiplayer, but was so well designed, it's still selling.