We're up to 7 million according to the CDC, not 10:
> Worldwide, tobacco use causes more than 7 million deaths per year[0].
Sagan predicted 7 million in growth and we only saw 4 million. That's a ~40% overstatement. And in the very next sentence from the CDC:
> If the pattern of smoking all over the globe doesn’t change, more than 8 million people a year will die from diseases related to tobacco use by 2030.
While we're on the subject of skepticism and 'baloney detection' whenever somebody says X will happen in Y years there's usually a bit of baloney in there. It's a well-meaning practice to present bad scenarios to create social change but it happens so often that when somebody says "The oceans will rise X feet in Y years!" I get skeptical. Then I get in trouble for being skeptical which just makes me more skeptical...
[0] - https://www.cdc.gov/tobacco/data_statistics/fact_sheets/fast...