FSWiki used to be the basically only, reliable source of new features for me but wiki maintainers are not always up to date with new stuff.
Are you saying this just in general, or was there something specific that wasn't documented? Even when it is, though, without stuff like this, there's no real way to 'advertise' new features, I feel like. This is a good way to let people know that things have changed and there's new stuff available; no one is religiously checking all the table articles for changes.
The former.
In short, I learned about majority of new features from pillaging modpacks like JAD or BP, because teams of such mods usually consists of people of high technical skills [like Axem] or SCP members directly [like The E]. Sometimes FSWiki, sometimes me chatting directly with SCP devs, but still I frequently encounter new features in people's work I had no idea about.
Nightly builds pop-up one after another like crazy. There is no way to go through the all logs looking for the hot stuff. I have a feeling that many modders just miss the new features, because they have no idea that they even exist.
For example: Before I played Warmachine, I wasn't aware that multi-locking missiles are finally a thing. I remember it being discussed couple years ago.
There is no anykind of obvious bulletin for potential modmakers, that enlists new, fancy, available features. I have a feeling that most people simply copy stuff from BP or BtA for their own works... And many remain in the dark for a long time. Including myself.