This was obviously filmed in Germany, as the radio (Bayern 3) tells us. He is driving in the right lane, behind a truck, which puts him around 110 km/h (~70 mph). (This is rather odd for a Mercedes driver, but OK...) The 1s - 1.5s distance, although more on the low end, is rather normal in Germany, everything higher will be treated as a merging slot.
In the US traffic tends be something +/-10% of the speed limit. Which results to people not giving a fuck about only passing on the left hand side, at least in Texas. As a result, in dense traffic the left hand lanes will only move marginally faster than right lane.
On the other hand Germany the speed difference can be anywhere withing 200 km/h (125mph) and 90km/h (55 mph). In optimal conditions traffic is evenly sorted along the three lanes. Since the driver going 160 km/h (being a nice person), will let the driver doing 180 km/h pass, he will merge to the middle lane and back to the left lane. The result is that you see way more lane changes on an Autobahn than a highway. So unless you have really dense traffic the flow of traffic is very irregular or you are tailgating someone, there will probably always be sufficient space to merge in front of you; if you keep 2s or more separation.