I mean come on, anything can be done without it and using blockchain just bring unessential minor improvements like decentralization that no one cares about. Prove me wrong ...
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.
Imagine if a notary, post office, etc. set up a signing service: relational database, basic signatures for user-submitted hashes, etc. Not quite as good but much cheaper to run and much easier to have trusted by a court — I suspect most users would see no additional advantage by adding a blockchain.
The centralised approach described requires that one trusts the database administrator. For a lot of things (probably the vast majority), this is good enough.
For the rest, there's decentralised distributed immutable ledgers.
Trying to explain something like Bitcoin just seems like you’d have a hard time meeting reasonable doubt standards in a dispute but that’s not the only model.
In July of 1610 Galileo was still making discoveries faster than he could publish descriptions of them. On the 25th he discovered that Saturn was apparently situated between two smaller companions that always moved together. Wanting to establish his priority of discovery, but not yet ready to reveal what he had found, he sent to Kepler (and others) the following jumble of letters, which he informed them was a coded description of his latest discovery (...)
Most of the discussion today about crypto developments is centered around bitcoin. But just because something utilizes a blockchain doesn't mean it has anything to do with bitcoin. Bitcoin was the first popular application built on top of a blockchain, and arguably the most radical.
The answer seems to be that repressive countries haven't yet put in place effective mechanisms to be repressive with respect to bitcoins. But there's zero reason intrinsic to bitcoin to expect that to continue. On the contrary, since everything is digital the choke points are easier to control, not harder.
The thing is that restricting bitcoin is really hard.
There are use cases for big money transfer and just "storing" money in BTC, not really for daily transactions.
The reason it was impossible, until recently, for an Iranian to open a bank account in Switzerland was not because of the Iranian governments, it was because the Swiss bank was afraid of running afoul of the US sanctions regime. Because those sanction have been lifted (at least for now) an Iranian can open a bank account in Europe, albeit they'll still have to go through a fairly extensive KYC process.
I don't think it's a lag thing - decentralized cryptocurrencies are just hard for governments to stop. Similar how governments would like to stop people paying cash in hand and avoiding tax but have never really been able.