Like almost all plants I will assume that the coffee plant is many hundreds of millions of years old and has lived through many epochs of far warmer global temps than the in present.
The “analysis” also completely disregards the likelihood that coffee growing will become economical in areas where it is not currently. Rather than becoming “extinct” (roughtly 0.0% probability) coffee would likely entend its range further north.
I can’t wait to get an nice cup of Green Mountain Coffee, that’s actually grown in the Green Mountains. About the only thing they grow there now is smelly hippies.