I work in this area and to me, the tech is still super interesting. In particular, things like zero knowledge proof and related scaling/privacy solutions are at the forefront of cryptography in my opinion.
My impression on the other end of it is that the "tech" is interesting in a purely academic sense but most of the participants are building things they know have no use and engaging in a lot of motivated reasoning about the future to justify drawing money in from the outside.
Like, it can all be a lot of fun! And some techniques, like all ZK folding schemes, are mathematical magic. But, no one wants code to be law and pretty much no one should be managing private keys tied to money.
It's a very cool but failed idea.
Those techniques were already invented and in-use long beforehand though.
I think that needs emphasizing, because sometimes it feels like... Imagine that fans of the Segway claimed it will replace all other forms of transportation, and a worrying number of them are still out there crediting the (failing) product for inventing the wheel.
Newer techniques like Verkle trees, SNARKs, STARKs, &c are.... well, new.
It's kind of like ride-share services: They didn't invent cars or databases or dispatching systems or phone-apps, and while their investment might have spurred some new tools/libraries/algorithms they use, the broader usefulness of those inventions doesn't flow backward to mean they have a good/sustainable business.
There are even cases like "private blockchain" where the fad-marketing is getting used to mislabel what is actually just a regular old distributed database of yesteryear.
Can we really call the car an "invention"? After all, both the wheel and the steam engine already existed.
Those techniques were already invented and in-use long beforehand.
I think it's important to give the cryptocurrency industry credit for the few corners in which it makes real (theory/tooling) contributions even if they're motivated by nonsense
You can do general purpose programming in all kinds of DSLs and Rust libraries that compiles down to big-but-practical arithmetic circuits and then generate proofs that y=f(x) without revealing x for arbitrary f. That really wasn't possible until a few years ago and emerged almost exclusively within the sphere of cryptocurrency-adjacent research. You can also use the succinctness of SNARKs to batch these proofs and shrink the verifier costs to almost nothing
It's a cool model for asymmetric computing, with low capacity verifiers collecting results from high capacity provers. It'll probably find uses outside deranged gambling...
The problem is that anonymous payments are essentially illegal under current regulations designed to protect the large incumbent businesses.
Cryptocurrencies could render paywalls and signupwalls a thing of the past, allowing you to pay a fraction of a penny for a page view automatically in browser without an account.
Such systems are illegal.
We see the issues with it: 1. It moves the trust issue or 2. The trust is only on the Blockchain.
World exists in a physical world which doesn't allow you at all to use a Blockchain there.
And zero trust for your money also means zero recovery