Love it. Well said.
I've recently read something that captures a core philosophy of the web in general. We start with tools (like databases, utility software, etc) and build on top of those tools to create services (social media, SaaS software, search engines, cloud services, etc).
When you move from a tooling space to a services space, you start to concern yourself with 'state', and he who owns the most state wins. As you mentioned, our private data, user behavior, interactions...that's all state. And companies that capture the most state incrementally and disproportionately grow to become monopolies.
We started with a decentralized web, and hello, we're more centralized than ever.
The Blockchain (which is functionally a database, sometimes preconfigured with its own computer, like the Ethereum Virtual machine) allows state to become open, and therefore not centralized. This will allow the idea of composability (one of the fundamental principles of the web) to fourish.
We're just getting started. I don't know what Web3 will eventually shape up to look like, but it's brimming with potential.