Humans extinct? Probably not, but
How does arguing the point that a portion of humanity will somehow figure out how to adapt to increasing heat, violent weather patterns, drought and crop destruction, shrinking polar ice and rising oceans, soil erosion, aquifer draw-downs and poisoning with fracking chemicals, oceans poisoned by oil spills and dispersants, ocean dead zones caused by fertilizer runoff, ocean water acidification and reef destruction due to CO2 absorption, make for a win in the argument?
How does arguing that if there are folks crafty and sturdy enough able to hunker down in Iceland or elsewhere where their food crops aren't incinerated by July, that humanity will have triumphed in the face of adversity, no doubt singing "I Will Survive", and we can all breathe a sigh of relief?
We are witness to what should be the biggest news story in human history but isn't, because of chortling deniers, Pollyannas who believe there are miraculous tech fixes for everything in paragraph 1 waiting just around the corner, business and its political shills clinging to the status quo, and a populace that holds more fascination with YouTube than science.
= new reply since forum marked as read
Your's is as valid an outlook as any! 
on edit: I used to think a good sci fi story would be God as a do-it-yourself'er & we are just some forgotten experiment in his garage.
