Merkel WAS a genuine innovation, and it DOES collapse into plain blockchain if all 'nodes' on a given tree have one child, because in this case the directed graph (tree) is a linked list. If the key innovation in both structures were not the same then your snarkyness would have been appropriate.
The point is that there is more to blockchain technology than just Merkle trees, I think. Just focussing on the underlying datastructure is like saying filesystems are just B trees or something.
Yes. I think that there a bunch of interesting ideas in blockchain technology, not all of which are necessarily new, but they are often new to the blog writer and/or audience. So introductory articles often focus on those basic concepts, which leads to this confusion
The Wikipedia article on blockchain has this sentence: "From the technical point of view a blockchain is a hashchain inside another hashchain", and that sums it up. The actual blockchain algorithm itself is as simple as that. Period. Full stop.
Of course, most actual APPLICATIONS of blockchain also ADD ON a lot of other concepts, like distributed ledger, distributed consensus, etc. Trust me, i'm not the guy in this conversation confusing algorithms with applications.
