Which current applications of blockchain technology seem most promising?

For clarity, blockchain is one type of Decentralized Ledger Technology, but not the only type.

Although those in defi seem well established, those that seem most promising within blockchain are cold chain, agribusiness and customs and supply chain related.

Blockchain went through multiple iterations in terms of how it can be applied. Crypto is currently one of the most prominent applications, but blockchain is also changing the landscape when it comes to legal and governmental matters. For example, the state of Illinois is issuing their own blockchain technology to trace residents’ ID, including their voting ID and birth certificate. It’s going to be interesting given the contentious nature of patents and their evolution. We’re already seeing a bunch of private equity companies in that process, especially in biotech where there's a lot of sensitive, private information. In biotech you want to be able to track who owns what, so blockchain is a phenomenal technology to apply in that department.