The point isn't that cancer doesn't matter. It's that by putting cancer warnings on things with a 1-in-a-trillion lifetime chance of causing cancer, you desensitize people to cancer warnings on things that actually do pose a significant cancer risk.
There is a whole philosophical bent about what "good" intentions might be which is way off topic.
When the side effects for ibuprofen read similarly to those of far more dangerous prescription drugs, then they're really not helpful