The utility of decentralized blockchains is that they facilitate permissionless financial innovation. Yes, that means "regulatory arbitrage". But not just circumventing the law, more importantly, circumventing the de facto law of corporate gatekeepers.

A substantial amount of de facto financial regulation comes not from democratically elected governments, but from companies that gate-keep access to the databases where financial truth resides. A great example of this is Visa and Mastercard dropping PornHub as a client. But there are many others. Building software that interfaces with money is extremely difficult, what you can and cannot do is extremely limited, and you may only do so at the pleasure of the major financial institutions that sit between your code and the traditional financial system.

Right now, if you want to write code that manipulate's someone's money, you have to ask the permission of both the owner of the funds, and several intermediaries along the way. What those intermediaries choose to allow you to do can be arbitrary, capricious, and certainly is not democratic.

It is true that decentralized blockchains also facilitate the flouting of the law, and that can be good or bad, depending on your point of view. But fundamentally, having an open fabric for finance, in which anyone can build any kind of application they wish, seems like a pretty cool thing to me.