Yawn. Non-telco(*1) Tier 1 provider declines to carry routes for an entity they don't like. Happens all the time. This is why you buy from a Tier 2 instead and bypass DFZ(*2) politics.

Drop routes from spammers: Spamhaus DROP list. Drop routes from DDoS sources? All the time.

Even Google wasn't reachable from Cogent over IPv6 for years because of a business dispute. For all we know someone working at HE was targeted by KF and this is a security response (also generally allowed even if you are a regulated provider).

*1: Cogent & HE thread the needle around being a common carrier (they don't sell voice or TDM service) or a broadband provider, which is why KF's WA state complaint will fail (WA's law only applies to mass-market retail providers, which HE is not).

*2: Tier 1 does not mean "best carrier" it means "carrier that doesn't pay another carrier for routes." DFZ literally means default-free zone as in they don't have a default route to another provider.