There hasn't been a significant improvement in social forums in years. Meanwhile Reddit has effectively destroyed the community at large, with the help of thousands of tiny servers which have divided topic-communities. The result is that people aren't really meeting or talking to the best of our capabilities.
I think we're in the middle of the evolution of forums. A big trend in open source software lately has been "Federated" services, allowing people to configure private servers which can communicate together.
There's a precedent for this. Back in the 1980s and 1990s we had something called "FIDOnet", which allowed single systems to share their posts globally.
I'm wondering if there are any plans currently to add some kind of Federation feature to phpBB, and if not, then I want to suggest that feature be added. This would allow people to have a single account on their favorite forum, while participating in topic-discussions across thousands of servers globally.