Events to encourage social cohesion seem like an obviously good thing to me, and having them annually seems to be very helpful for people in consciously experiencing the passage of time. Grieving, spending a moment looking forward, stuff like that.
I'm not fond of religion, wasn't raised in it but you know religion wars, scandals, etc. But one day I realized that a lot of 'modern life' was being laid on a couch alone watching low level distraction and ads. Suddenly, the idea of sitting with you neighbors listening to latin spells from a wiser (allegedly) person felt like quality time.
few ideas: i guess we won't go to religion but maybe groupism (just being together)
also i often think climate change will force that on us, less means and more challenges => deeper social link (unless violent political structures win first)
But some data would have been neat.