It's sort of a difficult question.
I feel like modeling is more based on natural talent. No matter how hard I try, my models suck ass. Some people just really are good at it.
Scripting is like complex math. If you're smart, it's easy. There's just a lot of syntax and whatnot to learn, but from that point it's pretty straightforward.
Intellectually, scripting is more challenging. But I do feel like modeling is not 'easy'.