This entire post seems to avoid or lack the understanding of the basic reasons blockchain were created; that is, to offer a decentralized, permissionless, censorship-resistant network. This was Satoshi's vision, and those values are a blockchain's express priority over scale and efficiency. Centralization is great for speed and efficiency, not so great for protection against authoritarian actors (governments or centr…
But what is it actually used for? Okay, you can donate to WikiLeaks ... But probably 99.999% of people who have possessed cryptocurrency are just speculators: buy low, sell high. And ironically, the exchanges are centralized entities :p
Everything is speculation (you hope it goes up in the future, but no one knows for sure), but large corporations are increasingly keeping a balance in Bitcoin, as are wealthy individuals and fund managers.
To understand its place in the world, you need to be a bit more familiar with government bond yield and risks, money creation/monetary policy, the macroeconomics of perpetually rising debt and negative interest rates.
Gold has a $11 trillion market cap, and its not because of industrial use or because it sells well as jewelry.