Blockchain is just a technology, one shouldn't have such strong feelings against it just because one is a contrarian and lots of idiots are shouting that it'll end world hunger or building scams using it.
You speak of machine learning and cryptography, both are tools, some use ML techniques to discover tumors in medical images before humans can spot them, and others use it to analyze your data to know which product should be advertised to you to make you spend more money on useless things.
I am definitely a cryptocurrency contrarian, so I was going to stay out of this thread - it wouldn't help OP to have people questioning his fairly straight-forward request.
But I don't think there is such a thing as "just a technology". Technology comes out of people's desires, and you can't disentangle it from the context it's created in. You can argue that blockchain is just an append-only database, but that ignores all sorts of externalities its adoption is causing.
