>Why are they attacking it so bad?

I can think of many people who don't like a potent OS-INT resource.

An academic once told me a story about how they had to pull out a wayback of a company's privacy policy, because when they called them out for violating it there merely edited the policy to make the behavior ok. (Without changing the "last updated" date)

It's also a potent censorship circumvention tool -- if you aren't willing to block all of IA, then it's a way to access a lot.