Sure. But how much more mechanics and lore will Spelljammer need to pack in? A lot more. The only other option is to do it half-assed in print and offer DLC like they did with Witchlight. Or split it into two books. Like Ravenloft. I'd prefer if they went the Ravenloft route rather than the DLC. But my gut is telling me they're going DLC. The question then is: which section is removed for space and booted to the DLC? Probably whatever's least useful for the most tables.
Exactly. So in a Spelljammer adventure path, what's expendable like the lore of the feywild is for Witchlight? At a guess, the lore of the setting. So we'd get what...an adventure a la Witchlight, with races and maybe rules for ships. But unless ship-to-ship combat is central to the plot of the adventure, it could also be shunted off to DLC. There's no way to cut content that doesn't end with the print product being half-assed.
I think you're over-estimating the page count necessary to fit in the Spelljammer rule set. There's no need for a lengthy gazatteer, which is often the real space-grabber in most setting books. Especially if a hypothetical adventure covers (presumably) Realmspace and the Rock of Bral within it. Races, ships, bestiary, some charts to roll random crystal spheres, a list of known crystal spheres with maybe one or two given some detail, and, what, maybe 10 pages on the basic rules of the setting and combat therein. It could all be covered in maybe 100 pages or so...
Yeah, that's exactly what I mean by half-assed. Eberron was too short. It should have been two books, at least. And a third book with an adventure path. Ravenloft is still less than half done with a full setting book and an adventure path in one domain. The Spelljammer monsters alone would fill a MM-sized book. But that's mostly due to WotC's choice to use ugly space-eating statblocks. All the ships and rules for ships. That likely needs about 100 pages. Without that "lengthy gazetteer" it's almost not worth doing.
That does not compute. You don't need to have an adventure that touches on every single world you can reach via Spelljammer, but yeah, you'd want...I'd want it to be a grand and glorious gonzo romp across the Phlo. If you're not going to lean into the setting, why bother? I mean, really, if there's no ship-to-ship combat, no gith pirates, no mind flayer nautiloids, no neogi slavers and umber hulks, there's almost no point to it.
