I worked for a blockchain startup and left with PTSD (I was asked to leave).

They had started as yet another ICO and when that didn't work, pivoted into a financial space that actually was a great pitch for blockchain.

They were a small company and when I came aboard they had nothing viable, I helped them rearchitect it to something that could work, and the lead ops guy translated it back to the original broken architecture.

That guy was crazy, and claimed that everybody there was spook adjacent (ex NSA, etc) and that our tech was vital to some secret need. They all drank the koolaid.

I do like the concept of blockchain as a "commons" of data, but stil think that cryptocurrency is a colossal scam.