Word of mouth, independent websites, newsletters, blogs, community organizations, religious organizations, political organizations, amateur radio broadcasts/transmissions, neighborhood meetings, festivals, conferences, meetups, cultural traditions, leaflets, town criers.
Every single one of these has been effectively used to organize at geographic scale within this most recent century before "non-technical" even existed as a possible descriptor of a human being.
Many of them necessitate going outside, which may present an imaginative hurdle.
Imagine electicity in the home is made availiable but the deal is you can have it only if you don't use said electricity to exercise freedom of speech against the government, e.g. use a lamp to help you write the speech. And they have a way to track you if you do. And the alternative is no electrcity.
Online services like email and social media even are utilities.