What is the inherent spirit of the law in only eating animals that chew their cud and have split hoofs? Or fish that only have scales and fins? The inherent spirit of not wearing linen and wool together?

There are plenty of places where religious jews go beyond what the law says because rabbis have deemed it important. The prohibition of not eating meat and milk together come from "not eating a kid in its mother's milk" but rabbis said it applies to all meat and all milk.

I'm not sure how legitimate it is to think you know or can determine the spirit of religious laws you don't know the details of.