I know you're getting dragged in the comments / downvoted, but the premise that the internet is not a fully reasonable 'third' place has some rationality, as does the premise that churches have been this 'third' place for many. And I think 'third' places are where leftist community-engagement thrives, even in religous settings.

I mention leftist simply because many here are commenting from leftist Lemmy instances, myself included. Historically -- and for a moment, consider this outside the typically nonreligious, leftist approaches to community building -- churches have occupied a helpful, physical 'third' place like this for centuries.

When they are healthy, churches have been relationship hubs of solidarity and mutual aid. They have also been regularly used platforms from which to mobilize for social justice and collective action -- even today, I know of some churches that are engaged directly in social justice and collective action for queer communities, debt reduction / removal, resource sharing, and more. Liberation theology is gravely leftist, as well, and comes from Latin American churches with leftist clergy and non-clergy at the helm of both theory and praxis. The Civil Rights Movement was borne out of black American churches, and suffrage movements met in churchhouses as much as anywhere else. This list goes on.

Liberation / radical inclusivity activities can spring from any setting where people gather regularly and talk about change. While the internet can make that sometimes easier, it has been historically in-person, where folks gather, that these movements find momentum time and again. 'Third' places are historically and functionally physical.

Theory is great for the internet, and even some community-engagement through internet discussions on theory is great. Some, but not all.

Praxis happens offline, though, in anti-technofeudally controlled arenas.