IMO, blockchain technology is good for one use case: illegal transactions.

If the friction of translating your fiat money into cryptocurrencies and back is low enough it can be a very good method for collecting digital donations. Potentially no fees to send/receive money, no real national restrictions to speak of and then its stored as a value that the recipient can use however they want, plus donors can trace where the money goes if the person they donated to then turns around and donates a portion to another person receiving donations on the blockchain.

Basically the exact same benefits as the use case of illegal transactions, but at least for good rather than usually-not-good