I guess the internet guides are more worried about telling you how can you get the infrastructure required to sell internet to others, which is being an ISP -- but it is philosophically different from being a "self-sovereign internet node" which seems to be what you want.

I think the answer is that there is no such thing as self-sovereignty on the internet, it's a set of relationships based on different interests, not very open, and very very hacky, and ultimately you depend very much on your peers, you can't ever be independent in any meaningful sense.