I explained why not in the sentence directly following the one that you quoted. Here it is again:

Let someone else who's purpose is fighting those fights take it on and stick to preserving those precious archives out of harm's way.

To explain in more detail: The Internet Archive is custodian to an irreplaceable archive of Internet history and raw data. If they go and get themselves destroyed at the hands of book publishers fighting lawsuits over ebook piracy, that archive is at risk of being destroyed along with them. Or being sold off at whatever going-out-of-business sale they have, perhaps even to those very giant publishers that destroyed them.

That is why not them in particular. Let someone who isn't carrying around that precious archive go and get into fights like this.