I appreciate Dagnir's point, but I see it differently. Not everyone's here for the crowd. Some of us enjoy the grind and the brain-bending challenges. That's the thrill of it, right?
Remember, FOnline was born out of a love for Fallout and a desire to keep that world alive in a new form. It's always been a passion project driven by a community of enthusiasts. That spirit is what's kept it going for almost two decades now, despite any splits or disagreements that have occurred along the way.
I think one reason for the dwindling numbers of FOnline is due to the game being so outdated. If this were to be recreated in Godot or a similar engine - and don't get me wrong, this is a mammoth of a task that will undoubtedly take years even if the scope was greatly reduced - then perhaps that's when it will begin to attract new players to the classic games. This goes not only for attracting new players, but also developers, because the SDK is so outdated now with clunky tools and using a shitty scripting language when there are many better languages today for this like C#.
To the OP, I appreciate your vision. You're right - the community's fragmented, the engine's outdated, and FOnline needs a serious revamp. Building something on Godot or a similar engine is a mammoth task, sure. But is it impossible? I don't think so. Whether it's worth it is a different question - and I would say it only seems worth it if you are thinking about the journey rather than the destination, because you may very well never get there in the end. There's also the point that if you're going to put this amount of effort into recreating the game in another engine, then why not start your own IP?
I would suggest an initial goal of getting a working demo in Godot. Port some assets, create a couple of maps, design a single quest, make it single-player. This gives us a tangible target to aim for and breaks down the mammoth task into more manageable stages. Then, we can build from there. It doesn't have to grow into another FOnline, instead it could form as the basis for fan games, not unlike what I believe cvet's goal is with his work on the FOnline engine nowadays.
The question I would have is what are the legal implications of this? You already see in ambitious projects like Skyblivion and Fallout 4: NV, they're having to recreate the assets and voice acting due to copyright reasons. Same goes for Take Two taking down Grand Theft Auto mods that port maps from one game into another.