A git history is a "blockchain" in the strict sense (A Merkle tree with branching factor = 1), so it's not a very helpful term. Bitcoin, at least, has the common decency of having a very concrete innovation as part of its value proposition, so you can discuss its merits. "blockchain" as a term used in the industry at large means so many different things that it ends up not meaning anything at all.

But he's right - most of the properties of the blockchain are not novel. Distributed consensus is the novelty, which is part of the problem with people talking hyper-enthusiastically about applications that either don't require, or don't allow it.