This is a hobby project where people come and go (sometimes briefly, sometimes permanently), there isn't really a goal to reach (aside from any personal).
As such most of the people working on it only spend a few hours a day/week (when not working etc.).
The engine is almost a separate project from the scenario (story/mechanics) as it can be used to make a different game (scenario), and the people working on it don't really touch the scenario.
Rather than optimisation (which also happens), the engine side fixes engine bugs, or adds features requested by scenario side/community.
On the scenario (story) side there were a few people mass-reworking event logic (because it was very inconsistent/messy), one of them vanished a few years back.
The rest made some decent progress on that (internally), however with the website being down we don't have any way to reach them. So currently there's nobody on the scenario side that we're aware of (on discord).
Aside from Umgah (who joined recently to make some scenario mechanics more modular/moddable/expandable), me (I have interest in things other than story-writing), and Shilo (main engine dev).
Changing/expanding story lines is the exact same process as modding the game (and it's one of the easiest games to mod).
Anyone is free to make mods for it, including storyline expansions or new storylines. So long as they stay within the themes of the game (don't completely flip things out of nowhere) and have a degree of quality, they can ask to have their work included in the game.
People that are considered 'trustworthy' (been around for a while and contributed) can even ask to join the internal event team.
Heck, I could probably just adapt someone's story text if they don't want to touch the Visual Event Editor (VEE) - provided they'd stick to a specific formatting ruleset.
Tl;dr: We might need more writers. At least more than the potential 0 if the others don't find this thread.