The post didn't name specific companies or products, but on that note, is there a list of sites that Chrome and/or Firefox have pinned somewhere? I don't think TACK has been implemented in them.
The thing with TACK is that it doesn't actually solve the key distribution problem. The draft itself states:
TACK pins are easily shared between clients. For example, a TACK
client may scan the internet to discover TACK pins, then publish
these pins through some 3rd-party trust infrastructure for other
clients to rely upon.
Keywords: "some 3rd-party trust infrastructure"That is what DNSChain and the blockchain provides. It provides more than that though, and thus providing everything that TACK proposes too.