No. Data is stored on your PDS and no one else can shut it down, there is no central server. The only difference from public atproto is when you ask someone else PDS for records in a space you need a token signed by the space authority to show that you have permission to read them.

ATProto is basically old web where you host your own content and advertise an RSS feed except there are aggregators that make everyone’s feed into one big firehouse that you can filter down to content you want to follow, and then view the content with whatever client you want (AppViews which are also servers but they can be pointed to a feed made up of others servers, like a Web Ring!)

I could hate on them for reinventing the wheel but the cryptographic stuff they do with signed merkle trees is pretty clutch, it’s a tricky problem to untangle public key identities from domains so you can migrate your content without losing your identity. There’s still not a good flow for that but at least there’s the groundwork done.

That's directly addressing vendor lock in