> Being angry at them won't change their behaviour

Yes, but the comment above was about society collectively making a decision, so that's the context I responded in.

And while it's relaxing to not worry about your own exact speed, I don't see how that lets you avoid stressing about the people that are lane-weaving. They're acting dangerously and I need to be ready to react to them.

Unless they careened into your vehicle while making the lane change, just calmly allow your vehicle to drift away from theirs until you have a safe buffer again, and take joy in the fact that it didn’t meaningfully impact your arrival time, but you’ve meaningfully impacted the safety of your immediate surroundings.