Al Gore was trying to point out a fact that it's each one of us as human being who causes the global warming, and it's up to each one of us to take action to curb the trend.
It is a truth that people and governments have been refusing to believe, not because it's wrong, but it's inconvenient if we take actions. As such, the truth is ignored, becomes a myth, and sometimes forgotten.
I think the issue Al Gore was trying to bring up has different context in China from US and other English speaking world, which benefit more from the industrialization, and hence the word "inconvenient" would have more "punching" effect as the title, but less so if using "麻煩/棘手“ in China.