I still don't understand. What is the solution? Just for context, I despise facebook and genuinely believe they are nothing, literally nothing but a drain on society. But. . .
I don't see a more accessible option. Facebook is as close to ubiquitous and universal as you can get, really. If someone cannot, not won't as the original poster said, but simply cannot access facebook, what other option is there? That means they have no smartphone, or internet access, at all. Therefore, there are no electronic options that exist. Physical paper mailers home? If they cannot afford a smartphone, what are the chances they have a permanent residence? Or, what for the parents who have no permanent residence. So that's not a solution. Next option - in person group meetings? Work, kids, health, transportation, any number of things exist that could be a barrier there. So what's the solution? That's not a flippant question, that's a real question. I don't see it.
Again, accessibility should be about ensuring everyone has the opportunity to access the goods and services in an equivalent way. Not about ensuring everyone gets to access the goods and services in the specific way they want to.
This all started with OP originally talking about not wanting a facebook. Not to sound too hateful, but part of living in society is understanding that certain personal concessions will have to be made. Like it or lump it, decisions have consequences.
Maybe I've gone too far off the path, but I think it's all related.