I'm not sure I understand the question. Regardless of what provider you choose - be it cloud based or local - you have to provide setup information such as host, authentication, etc. So it "defaults" to nothing; you have to select something.
Maybe this will be a clearer question: What does "local-first" mean in the title that you typed in for this HN submission?
Maybe this will be a clearer question: What does "local-first" mean in the title that you typed in for this HN submission?