Bit hard to get notified by the ISP if you effectively try to side-step the way they notify you, don't you think? Also bit weird to blame them for that.

If I recall correctly, if you try to access the IP directly you get the same notification. No football game on right now though so cannot check.

Edit: In fact, I'm not sure they do DNS filtering at all actually, it may be just based on IP, can't remember off-hand, considering the collateral damage, I'd say IP blocks mainly.

ISPs have your contact information, and they can also put up notices on their own website. Hijacking somebody else's website with forged replies isn't "the way they notify you," it's a man-in-the-middle attack, and users shouldn't be trained or encouraged to accept it.

Hijacking secured connections to inject a payload that doesn’t actually come from the source is not a legitimate form of notification - it’s a malicious infrastructure attack.