Right now, Nino Schurter and Scott's pros. Someday soon, us mere mortals. This bike is for the folks who need cutting edge and aren't afraid of the early-adopter tax.
We don't know yet. The press and Scott have been tight-lipped. But we bet there's going to be some fun to be had now that 32" wheels seem to be making their way over from mountain bikes to gravel.
CX and gravel racers who size like a road-race bike. If you want Future Shock and mounts, Diverge is the sibling.
The light gravel/CX race bike: lower and snappier than Diverge, with less adventure hardware. It feels like a Tarmac that grew tire clearance.
Gravel riders who want Giant's drop-bar all-road, not a TCR with knobbies.
Giant's gravel bike: stable, mounts, and a position between Defy and a race gravel whip. The X variants add more suspension/travel attitude.
CX racers. If you want gravel capability, look at Checkpoint or Checkmate instead.
A UCI cyclocross race bike with IsoSpeed on some generations. Tight, muddy, and built to be shouldered — not a Checkpoint with CX tires.