This is so true. I'm a practicing Catholic which gives me the advantage of having access to a big community and I even met my wife through Church events after Mass so it's wonderful. Also our Church offers many other programs like counseling, support groups, volunteering, career opportunities, etc. Of course no one should be forced to attend "Church" just to find a community, that's silly but its benefits are pretty clear.

However for non-religious people there is really no third place to meet. Additionally, the truth is that outside of religious communities, people are not having children and thus it creates a further sense of isolation and loneliness. The best one can do is perhaps join meetup groups for hobbies but most of those cost money and may not be welcoming to everyone.

I would also say that this can be a cultural phenomenon, for example in my home country (Iran) people are always meeting and socializing, at 10PM streets are bursting with activities and it's very easy to find people to connect with. In the west, unfortunately it's much harder and society is more focused on the individual rather than the collective so to approach a stranger in the street feels like a risk as they might consider your actions rude, disruptive or invading their personal space.