A frequent way of describing Bluesky's decentralization, including by Bluesky's team, is "it's like a bunch of blogs (Personal Data Stores), and then the relay/appview/etc pieces are like search engines"
This is a reasonable starting point for thinking about things, so let's run with it.
In fact ATProto's own tutorial even says "Think of our app like a Google": https://atproto.com/guides/applications
And indeed this is a good way to think about things. But it doesn't seem so bad, because we have Personal Data Stores like blogs, so probably things are fine, right?