I'll give this a shot. I've written variants of this comment a billion times on HN, but I sort of enjoy trying to create the perfect articulation of what it is that I like about crypto, so I'll try again:
Crypto is an alternative financial system. Financial systems, on their own, are castles in the air. They provide no value to anyone. Financial systems derive their fundamental economic value by being wired to the real world in some way. That is, efficiently allocating capital to productive enterprises, cheaply translating capital between different forms (e.g. currencies, but also product <-> currency), and transferring risk from those who don't want it to those who do. This is why finance exists, and what it is for.
The cryptocurrency financial system as it exists now is only very weakly connected to the real economy, and only in a few places of marginal or possibly negative social value (e.g. drugs, gambling, prostitution, ransomware). However, there are a few places that actually use crypto fairly heavily for legitimate, socially useful transactions, such as Vietnam, Ukraine and Venezuela. Most people here tend not to find those examples particularly convincing, and neither do I - but they are important to mention.
But what crypto represents is an alternative model for how a financial system could operate. It is a financial system that offers many of the same features that our existing system does, but is different in some ways. Asking "What good is crypto?" is a bit like asking "What good is Linux when we already have Windows?". They both do very similar things, but they do them differently, and most critically, they imply different distributions of power.
If you build your business around Microsoft products, that's fine, but in several important senses that makes you beholden to Microsoft. If you want to build a financial business in the traditional financial economy, you will probably have to go to one of the major money center banks, hat in hand, and ask them to let you do whatever it is that you want to do (or an intermediary that has done this). Depending on what it is you want to do, you may have to go to all of them and ask this.
Crypto is different. If you want to build a financial business in crypto, you simply write the code and deploy it. You don't ask anyone for permission, and there is nobody on earth that can tell you "no". Even the US Treasury hasn't shut down Tornado cash, they've merely sanctioned it. The drawbacks of this approach should be obvious, but so too should the benefits. Whether you like the approach crypto offers is simply a question of values. But it is, in my opinion, undeniable that it is meaningfully different while being capable (in principle) of offering most of what traditional finance does.
The fact that crypto has not yet been wired to the real economy is the reason that it has not yet provided much in the way of concrete utility in most developed markets. The reason it hasn't been wired to the real economy is that regulators and lawmakers mostly have not allowed it. And I agree with them! I would like to see a little more experimentation in that direction, but crypto is fairly obviously not ready for prime time in this sense - not yet, and maybe never. Many things would need to happen first. However, don't mistake the absence of this connection for the theoretical inability to create it. It hasn't been created because people are cautious about things this important, as they should be.
There is nothing in principle right now preventing anyone from tokenizing a house, or a corporate debt instrument. And even if you think "nobody has done those things because they're stupid and crypto is just worse than traditional finance", you may be right! But it should be obvious that there are enough crypto believers out there that this would have been done if it were legal to do so, even if it were a bad idea. Hence, given their total non-existence, it should be clear that the reason it hasn't happened is regulatory, not fundamental capability.
You will know crypto has failed if and when there are a few real estate titles, car titles, equity shares, bond instruments, and other assorted things from the traditional financial realm that have been tokenized, but nobody cares about them. Assets placed there by a few true believers, traded for a bit, and then forgotten. That is how you will know crypto has nothing to offer. But for now nobody has done those things, because the traditional legal system (correctly!) won't respect them sufficiently.
EDIT: To extend the Linux metaphor a bit, Linux was created in the early 90s, but I would argue it didn't become clearly economically significant until the late 2000s. Prior to that it was a toy for nerds and anyone serious used "real products" built by "real companies" and purchased for money[1]. Crypto is FOSS for finance, and maybe the traditional world is right this time, and when it comes to money walled gardens and closed ecosystems are best. But it's not the world that I personally want to live in.
[1] The exact timelines here are obviously fuzzy and certainly you can argue with whether it was late or mid or early 2000s, but what is inarguable is that Linux went through a long "just a toy" phase in the minds of most people