Seems you don’t have a X server available. If the Jetson has a local monitor but no X server running, you may try instead:
gst-launch-1.0 -v nvarguscamerasrc ! 'video/x-raw(memory:NVMM), width=640, height=480, framerate=30/1' ! nvoverlaysink
If the jetson is headless, you would need to connect with ssh -X or -Y for X forwarding from a host having a X server.