Just ONE car can reduce traffic jams. Try it: leave enough buffer such that when the car in front of you stops, you almost reach their bumper at like 5 MPH but never stop b/c it’s time for them to move again. The guy behind you may never actually stop too.
So you had all these stoppers in front of you, and several cars not stopping behind you.
Enough people do this, and there’s no more stop & go. Just cruise 5mph the whole time (not 10, 0, 10, 0, 10, 0, which sucks).