I don't think there's much need to store your personal data in a blockchain. I don't think that's the intended purpose.
I'm no expert at all, but my understanding of blockchain technology is that it's decentralised. It can't be destroyed or tampered with unless the entire network is destroyed. If someone tries to tamper with it, it detects it as invalid and can correct it. That seems to me to have some value.
So I guess the applications that might use it are ones that might be vulnerable to attack, or where lots of people need to have complete trust that no one is tampering with the data. I imagine that's why most of the current usage is finance.
I know people are very down on cryptocurrencies at the moment, which as far as I'm aware all use blockchains to keep a record of transactions, but I feel that they're an example of a good theoretical idea - decentralizing finance - coming into contact with imperfect, corrupt, humanity. I think some form of cryptocurrency will persist and ultimately be useful, it's just that it's the Wild West right now and things are still mostly lawless.
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It's dark. Is it always this dark?