For however "high-profile" they are and however competent their lawyers are, this is a form letter, sent by someone who doesn't even know what Boing Boing is.
While perhaps some rando HN commenter can profess to not know what an "ESR" is (above, and sure ok fine, insert xkcd here), it doesn't seem likely that Bird doesn't know what a Boing Boing / Doctorow is. But even if they stamped out a boilerplate takedown with Linda Kwak's attestation that she has ".. a good faith belief, and do[es] solemnly and sincerely declare .." then it's on her, that's the rules of the DMCA takedown game, don't hate the players.
It seems far more likely that Bird knows full well what they were getting into here.
If you are reading this I urge you to go to eff.org and smash that donate button.