Yes it is increased traction. Since without the swaybar, you'd have so much traction roll that you would lose grip easily from all that weight transfer. The swaybar does indeed help with adding more traction. Try driving a TC without swaybars on a track and check your laptimes. Then drive it on a track with swaybars equiped, you'll notice that you can turn faster laps since your tires will always be on the ground and efficiently transfering power and aswell allowing you to turn more sharply and overall have reduced understeer rather than not having a swaybar.