I don't know that it counts since it's not a "blockchain" in the sense most people describe it, but Git is sort of "blockchain adjacent." It uses a Merkle tree to maintain a crytographically signed quasi-immutable ledger of transactions.
While it's probably not a "blockchain", I don't think that anyone disputes that Git (and its blockchain-like feature) is useful.
I suspect that this is going to be the "good" that comes from blockchain [1] and its ilk; a lot of interesting uses are going to pop up using blockchain concepts, and it will be cannibalized into something that is indisputably useful.
I agree that there are a lot of crypto idiots who act like all problems will be solved by Bitcoin or Ethereum, and I do think they give the legitimate research being done on blockchain (e.g. the Ouroboros protocol) a bad name.
[1] I know Git predates blockchain.
Solved problem: Hyperinflation caused by excessive governmental money printing.
Yes, I know you may not consider this as a "problem", but tell that to the millions of people who have had to watch their life savings being erased to zero value.
Yes, the Bitcoin price may be jumpy, but we aren't yet seeing kids playing with bricks of trillions of Bitcoins because they'd be so worthless that you can give them to your kids as toys.
That DID happen with fiat currency:
Enter "hyperinflation" into your favorite picture search engine.
I personally own a 1 billion bill of a previous currency of my country which I bought for the equivalent of $5 on eBay.
I think you're referencing BTC in use as some kind of ubiquitous currency ? That would be an interesting use, until someone owns enough to influence the market, which, already happens, so it would make matters worse for more people
Meaning acquiring it fairly from the market?
As compared to fiat currencies, which can be issued and moved around with the snap of a finger. That's a net improvement.
Uhm, why not?
As far as I see, the price of Bitcoin has actually even hyperDEFLATED.
It started below $1! Now it is at $40000.
The non-"print more money" version will reject its blocks.
So even if they throw 90% of hashpower at it then it will not be the consensus because nobody uses a version of Bitcoin which accepts the blocks it mines.
The problem is that the "social ledge" value of a blockchain is hilariously expensive, to the point that governments look cheap in comparison. And a private ledge doesn't bring a lot of value into any application (but where it does bring a bit more of value, it is getting adopted, like version control systems).
There is value in almost every new technology, I think blockchain and co haven't gotten a bad rap thanks to the 'morons' who are basically just 'pumping and dumping' or 'hyping' to make quick money. Which IMO is a shame because it stops the real innovation taking place.
It could be something, but it's been given (rightly so) a stigma thanks to the cult of 'crypto bros'. So far a waste of potential.