If I made a groundbreaking discovery today, putting a sha-256 of it into the blockchain would be a very good proof later on that I actually owned it at this time.
But beyond that I agree with you. My (non-technical) girlfriend is looking into cryptocurrencies lately and she watches tons of youtube videos about it while doing her research (TEDx talks and the like). Easily 90% of the claims of "blockchain is going to revolutionize X" are easily dismissed either because the blockchain can't do what the person claims or there's an other, often simpler solution to this same issue. "Use the blockchain for food traceability", "use the blockchain to validate critical equipment firmware" etc... It sounds good as long as you don't think about it for more than 10 seconds.
The problem is that in order to realize that you need to have a rather deep technical knowledge about how the blockchain works, something 99% of people investing in crypto probably lack.