At the risk of displaying my ignorance and lack of knowledge about this area, one part I found very familiar in this article is that the action interactions in his apps didn't actually interact with the blockchain, but essentially with two centralized services.

My very limited understanding is that for blockchains essentially the way to distribute them is that every node has a full copy. This sounds awfully expensive in the long run. My intuition would be that once running a node is expensive enough, this would not be truly decentralized. If I can't get the fundamental information out of a blockchain myself on hardware I can afford, the actual properties of the blockchain don't matter anymore as I cannot access them myself.

The moment you need to rely on third parties, you lose any unique properties a blockchain might have. I don't know how this would work if blockchains inherently are inefficient enough that you always need a way around querying them directly. I find the idea of a distributed trust-less database interesting, but if it is so inefficient that I can't actually access it myself that idea doesn't seem that interesting anymore.