The author thinks that to be decentralized, you should have your own chain. Holochain has one chain per app, more similar to what the author wants. It's not exactly a blockchain though. There are quite a few other non-blockchain projects in development also.

Found an overview that shows non-blockchain projects. Not sure whether or not it's an accurate comparison of features, but it's the best of list I've found of alternative crypto technologies. https://i.postimg.cc/05RJqbYB/SN-Comparative-Analysis-v4-1-I...