My dude, you should find a better hobby than just posting on HN crypto posts to spread some FUD. I appreciate skepticism, but you have an axe to grind.
There are legal counterexamples, but the majority that come to mind are equally well-served with fiat. If you ask me to come up with a good, legal reason to hold cryptocurrency, I may well tell you that there is none even if there are a few marginal situations that justify it.
For blockchain, there exist some good (and legitimate) applications.
Cryptocoins otoh... lots of gray area there. If not outright Ponzi schemes.
I hope some day, some crypto coin(s) will fulfill their original promise. But that day is not today.
I really do feel the same about blockchains as I do about cryptocurrency. Both have extremely limited applications that appear marketable and attractive to nerd-adjacent circles, but only show their drawbacks once fully invested.
The intention behind creating a blockchain (or even some cryptocurrency) is pure in it's inception. The application of both technologies is so messy that I would recommend most people stick with simpler options.
Millions have lost money due to this pyramid / ponzi scheme, and people like you trying to justify it with nonsense ad hominems.
It is well documented that crypto absolutely has no legitimate use case whatsoever that works better than the current system other than speculation, ransomware, etc.
So it is just as simple as to say the fact that:
"There are none. Period."