Writers need to be interpreted, because it's unlikely that they actually understand what they wrote. Therefore, when employing a novel to address a problem, my interpretation is probably more important than the original work.
I believe that a vampire is a representation of exploitative forces that you invite into your own life but could avoid if you chose to. A policeman is hard to avoid, especially if they have a warrant. Therefore, a vampire cannot be a policeman in the first place, since the state of being a policeman overwhelms the state of being a vampire.
When do you think you should allow a child to have an email address?
A Fediverse account is basically an email account, except that the primary inbox is shared with a lot of people rather than only one person (and the same goes for any social media account). If you wouldn't allow someone to use an email address, you probably shouldn't allow them to use a Fediverse account either.
People probably realized that they should preemptively describe where they were soon afterwards, so asking about that was surely not necessary very often.
I suppose that, until recently, all communication methods made it clear to someone where the recipient of a message was. Someone getting a letter probably got it at a particular place or from a particular person, and even a phone call would often require using a particular device at a particular place.
Even if you didn't know where someone was when they received a message from you, it would be such an obvious question that people would probably provide it in a message to you even if they weren't asked about it (see https://greatships.net/distress and https://www.youtube.com/watch?v=FxRN2nP_9dA for an example from the Titanic). This makes me think that "Where are you?" actually means "I don't know where you are" / "I'm having trouble finding you" and is most useful when you can communicate with the person more frequently than they would announce their position (which might only describe situations when you're talking to someone using a cell phone).
As an alternative to making decisions without direct assistance, you might benefit from contracting with another person to make decisions based on requirements you describe (essentially getting a chief information officer (CIO) for yourself). The main reason I'm suggesting this is that having more people involved will make it more likely that someone will know about established best practices relevant to your situation or that someone will have experience with a problem that is similar to the one you're dealing with. Additional reasons I could provide for this would be similar to the reasons people give to discourage someone from handling court appearances without a lawyer or doing surgery on themselves. You might be able to use https://ryf.fsf.org/categories/laptops to find information about how to contact people about your computing needs. Alternatively, you could visit a store (for example, one operated by Walmart).
Does that already exist? https://www.privacyguides.org/en/real-time-communication/#briar I'm not sure how "decentralized" it is, but it is probably at least somewhat decentralized.