FaceDeer

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.

An innocent kid was on board the Titan, in case everyone has forgotten. He didn't want to go. Limit your laughter a bit.

It's possible for a stupid person to do or say something clever, though. You have to fight the battles that are actually before you, not simply imagine that they're already won because you think your opponent is dumb.

They're only at risk when they take risky behaviours. Simply archiving the Internet, like they've been doing for years, is not what they got sued over.

If they're going to keep doing the same thing they got sued over then they're going to keep losing court cases, because obviously they are. The definition of insanity is doing the same thing and expecting a different result. They should stop doing that.

It probably wouldn't help their current lawsuit, at this point. Maybe right at the beginning, before it went to court and they could negotiate a bit in search of a reasonable settlement, but at this point they've already lost it hard.

What it would do is reassure me that they're not going to do something dumb like this in the future, which would make me more willing to donate money to them knowing it'll go to actual internet archiving activities instead of being thrown into big publishers' pockets as part of more lawsuit settlements.

This subthread switched specifically to the topic of their pending lawsuits, it's not about the DDoS. I doubt the publishers are behind this DDoS because they're already easily winning in the courts, there's absolutely no need for them to risk blowing their case and getting countersued this way.

Who else is better equipped?

The EFF, for example. Fighting lawsuits for the sake of internet freedom is their reason for being. Sci-hub, for ebooks more specifically. Or Library Genesis. Those are organizations specifically devoted to fighting against excessive copyright restrictions on books.

Just because you perceive them as unworthy to bear the challenge

You're not understanding what I'm saying here. I don't think Internet Archive is unworthy to bear the challenge. I think they're not well suited to it, and when they inevitably lose the lawsuits they've jumped head-first into they're risking damage to other causes that are very important and unrelated to this particular fight.

doesn't change that IA is storing files, ebooks to be specific,

Emphasis added. Storing files is not the problem. Nobody cared when they were just scanning and storing them. The problem arose when they started giving out copies. And worse, giving out copies without restriction - libaries "lend" ebooks by using DRM systems to try to ensure that only a specific number of copies are out "in circulation" at any given time, and so the big publishers have turned a blind eye to that.

Internet Archive basically turned themselves into an ebook Pirate Bay, giving out as many copies as were asked for with no limits.

Again, I don't agree with current copyright laws, I think the big publishers are gigantic heaps of slime and should be burned to the ground. The problem here is that it's not Internet Archive that should be fighting this fight.

Did you read literally the next sentences I wrote after that one? Here they are:

Just not by Internet Archive. 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.

The Internet Archive is like someone carrying around a precious baby. The baby is an irreplaceable archive of historical data being preserved for posterity. I do not want them to go and fight with a bear, even if the bear is awful and needs to be fought. I want them to run away from the bear to protect the baby, while someone else fights the bear. Someone better equipped for bear-fighting, and who won't get that precious cargo destroyed in the process of fighting it.