This factors in some feedback loops which most sudies to date have ignored. Note, that it excludes extra warming caused by all the additional water vapour in the air.
For context, studies suggest that the largest extinction event in Earth’s history (so far), the Late Permian Extinction Event, saw temperature rises of around 8°C.
Hey, at least we won’t be around to find out what happens if you add PFAS, aluminum, microplastics and other nanoparticles into an existing species over multiple generations.
Don’t forget lead and asbestos!