Seems to me like there a broad spectrum of "self-hosters", ranging from "I run everything on my hardware in my home" to "I deploy FOSS SaaS software to AWS for us to run", probably neither of these are more/less "self-hosting" than the other.

Yes, so obviously as a self-hoster, that's a no-go. Hence not wanting "to enable a few services", it'd go directly counter to the initial objectives.

But yeah, I hear and agree that there is a spectrum here, self-hosting some parts while relying on others can be a good balance, especially if you have other requirements to consider, like time or resource investments, it's not a black & white decision you should make without careful considerations.