It's because most of these projects are fakes or scams. The real interesting use cases will be based on public blockchains like Bitcoin. In fact, the only way to write and store data on a blockchain like Bitcoin is by doing a Bitcoin transaction. People now are actively developing second-layer protocols—for example, Rootstock—that rely on the proof of work mechanism of blockchain to, for example, create smart contracts. Advanced technologies and advanced use cases like land registry and supply-chain tracking could be developed on top of the Bitcoin blockchain. With respect, I think the real revolutionary blockchain use cases will be built on public blockchains.
On March 19th, 2018. See this statement in context.