Swordflight would indeed be quite complicated to turn into a premium product, for a variety of reasons (use of third-party content, my reluctance to abruptly put something that has so far been available free behind a paywall, its sheer size, etc.). As I suggested, though, it would not be that difficult for me to make short modules (and many of the existing premium modules are quite short too) of reasonable quality if I had enough incentive to do so. I mean, I made
Snow Hunt in just one month, and while I do not think that particular module is all that spectacular, I also do not think it is
that much worse than some of the existing DLCs. Imagine what I could do if I had two months to work. Of course, that is all very hypothetical and I do not know that I would necessarily even want to work for Beamdog, but, again, it is not as if I were the only experienced NWN modder out there.
Just while we're discussing pure hypotheticals, to their credit, Beamdog did not have DoD removed from the Vault when they published the EE version, nor was the old, partial build of TotM taken down, but yes, it stands to reason that any development would be EE-exclusive. Obviously could be a problem with the last two Swordflight chapters, but a new, original module... hell, I'd be interested.
Yes, it does seem odd how little they are doing with NWN. Given how low their standards for DLC are, you would think they could churn out a lot more of it. On the initial release, they could really have used something more exciting for the average player than all the technical stuff they actually offered at that time.
This is pure speculation on my part, since we no longer have Steamspy data to look at, but I suspect that NWN EE underperformed commercially. The thing is that they rolled it out too early, without any killer selling point. The Codex approach to the Infinity Engine games is to "just mod it", but you do
have to mod them if you want to enjoy them on modern systems. This isn't the case with NWN Diamond Edition, unless you're one of those unlucky souls for whom it doesn't start at all, your biggest issue is small text at high resolutions.
There were two obvious features Beamdog could've pursued to entice buyers: a graphical ovehaul (characters at least) and full party controls of some kind. The former would've been costly but the latter is a systemic change for a couple of programmers to hammer out, and both were on the table at first, but they've slowly drifted right into limbo. The third possible selling point was new campaigns but we didn't get any of that until TotM came out more than a year after launch. DoD doesn't count, I did pick up the EE at that point just to kick some money Ossian's way, but the "free" version was already a complete and robust module.
Instead they went for the mobile market and complicated their pipelines, but that's not exactly the biggest market one envisages for diehard CRPG enthusiasts. Meanwhile the buzz fizzled and their own NWN EE forums are hard at work developing dustbunnies.
It could be that WoTC is being difficult about licensing their settings, but if so why they would make an exception for this Furiae module, of all things, is yet another mystery. Maybe because the Descent into Avernus connection makes it a tie-in with other products they want to promote?
Now there's the rub. In fact, I can't help but wonder whether there's licensing issues affecting more than just NWN EE efforts. TotM still hasn't made it to their own store, has it? Why? Did they run out of hard drive space? Funnily enough, they do sell the soundtrack for it. Also, the "big" 2.6 IE EE patch and that nasty pathfinding bug that 2.5 introduced, still pending after a year. They couldn't spare one programmer to make an interim patch? For a thing that a modder developed a revert to eventually? If it's release overheads that's the problem, just borrow an Owlcat developer, they can publish six hotfixes in as many hours. There's gotta be something else going on over there.
As for this Furiae module... Maybe a promotional tie-in by WotC to hype up their Baldur's Gate: Descent into Avernus book and indirectly, hopping on brand names, Baldur's Gate 3? Or maybe the opposite and it's just a quick buck that got greenlit due to WotC disinterest in Planescape, who can tell anymore.