Indeed tele lenses is not been a strong point of tech cameras, and zooms are missing.
However with a field view camera and nowadays discontinued Schneider Digitars one can get a quite compact and very flexible system. I carry a Linhof Techno with 35, 47, 60, 72, 90, 120 and 180mm lenses, and as the lenses are small and compact and all lenses use lens boards rather than barrels I end up with about 6 kilos (14 pounds) net (camera, back and lenses), and that includes a sliding back. Tilt, swing, and shift in all directions for all lenses. With tripod, head, extra batteries, water bottle etc and the backpack itself it adds up to say 10-11 kilos to actually carry around, but I think that's not too bad.
That flexibility suits my shooting style very well, although it does happen that I would like even longer reach. I've chosen to not get the 210mm though (which is the longest possible in the system) as it's a considerably heavier lens than the 180 and not so much longer. With roughly 30% spacing between the primes I don't really miss a zoom.
Unfortunately digital back development killed the small compact symmetrical lenses, and ground glass was too difficult to use to many so this type of system is legacy now. Had modern live view backs supported symmetrical lenses better and manufacturing continued it would have been a really nice field system for landscape photography.
A camera like the XF must support wide apertures and must have retrofocus lenses and thus they become very large and heavy. A tech camera doesn't need wide apertures and historically did not need to have retrofocus lenses and therefore had its special niche. But since all backs after the microless-free and pixel-shielded Kodaks have required retrofocus lenses it couldn't thrive, and now I think we've reached a point where the customer interest that actually existed for this niche has strongly weakened and people are looking to the other solutions.
I think the key selling point has not been flexibility but always been image quality, and when the majority don't see that they get a relevant image quality improvement over the more integrated standard camera systems the genre is in trouble. Personally the traditional/tactile large format style shooting experience is a key selling point so I can actually live with even a bit lower pixel peep image quality, but I think that view is rare.
Anyway, tech cameras are great for landscapes, and to anyone that's thinking about getting one I think it's sort of a "now or never" situation, so do get one and enjoy while it lasts.