When I'm criticising blockchains I often use the term "distributed consensus blockchains" in an attempt to avoid confusion with Git and certificate transparency logs and other useful data structures.
I'm pretty sure that if we researched the origins of the "git is a blockchain" meme we'd track it back to the community of crypto currency sceptics which I know you closely follow.
"A blockchain can be a useful data structure like the one git is using" isn't intended as a helpful clarification. It's an attempt to push for a change to the meaning of "blockchain" as originally (and currently) understood, to advance slight-of-hand arguments such as "blockchain was invented in the 70s, there is nothing really new here".