meetdilip On the other hand, with the pace of development as it is, Flarum is certainly relying on its community to pull the heavy lifting when it comes to feature extensions right now. That might change after stable, but for the moment the community is doing a great job at providing highly requested features, allowing our core devs to focus on the stability of the software itself.
It's possible what you say will become a significant problem as the software matures. For the moment, the amount of abandoned extensions isn't quite a bit problem, several were abandoned because their features became part of Flarum's core. That's not a general progression nor expected for all extensions, some will always be provided by third parties.
It's just a philosophy difference. Flarum considers all extensions equal under the sun, whereas other forums have packed their core software with the features Flarum offers as first party extensions.