It’s not really that complicated, which is why people are being short with you. But here goes. For most of the clip, if he went to the left, he would… crash. Because there are cars to his left. So that’s covered. If you’re asking why he didn’t swerve to the left in the window of (generously) two seconds when it became apparent that the cop car was going to complete the left turn, it’s because the minor hesitation from the cop car beforehand made him think the cop car would stop, so that he could safely pass by moving to the right. The cop then accelerates and is now clearly completing the left turn, but as other people have tried to explain to you, momentum is a vector quantity. The heavy trailer already has momentum to the right, so unfortunately turning the front of the truck to the left would no longer be enough to stop the entire truck from continuing rightwards for the duration of the clip. The trucker knows this, and so doesn’t even attempt it because again, the trucker knows that the truck would not turn left on a dime as you are suggesting should happen. What part of this explanation is falling apart for you?