I honestly don't see difference. Barely FS because of what? Because it has "only" 60mm travel instead of 100mm like most of xc bikes have? For me it looks pretty much normal FS bike. Of course there's whole bunch of PR on their site how IsoStrut is integrated into frame and therefore super light. But bike is still less then 200g lighter then for example Canyon Lux... based on Canyon/Trek statement, which is of course impossible to compare as depends on size, equipment etc., but just frame, which still depends what size they weighted is 1.66kg for Canyon Lux and 1.96kg for Trex Supercaliber, which means it's not all that light. Unless, which I would assume with such weight difference, Canyon weighted their frame without rear shock, but with standard shock for this bike (Fox Float DPS Factory) would add 250g, making it 1.91kg
Just based on this what I could see on web about IsoStrut I would say it's really just visual thing compared to other similar bikes. Sure outer tube of "suspension" is fully attached from and back on frame, but that doesn't play role, as seat stays are still attached to shock only, similar to any other bike, which is normal as otherwise suspension wouldn't work at all. Rear pivot is nowadays pretty much exception and not rule for most of modern xc FS bikes, as most of them have "flex pivot" or whatever certain company calls it, exactly same thing that Supercaliber has now.
Again, I certainly don't know anything/enough about suspension, but I'm fairly technical type, so just seing this, doesn't really make me thing it's anything but very short travel FS bike. And even that not so super short, as 60 vs 100 is still not that huge difference. And nowadays with remote lockouts I definitely don't see issues with 100mm rear travel, but when you unlock it, 100mm rides faster on downhill then 60mm or 0mm.