1) That's per 250 kcal. A plate of pasta has significantly fewer calories than a plate of steak. Sauces on either can alter this, but they'll likely have their own indices to pay attention to.
2) The low ends are equal. The high ends are off by a factor of 1.5.
I think that the real question is "What will happen to my insulin if I eat a meal of pasta vs, a meal of steak?". To that, I think that the steak will in fact spike your insulin much higher than the pasta.
That said the beef has a higher satiety score (by almost exactly the same ratio as the high end insulin ratio).
Again, sauces, what your body needs right now, what you'll eat for your next meal,... lots of things can alter the overall health perspective.
