Yes the speed is remarkable but it has still been much warmer or colder over a longer period.

This is precisely the point that comic is making tho. Yes, our planet has been a lot warmer than it is now, but as far as we know the changes we're currently making to the climate are by far the most rapid in human history and this is bound to cause some civilization-scale issues. Even ignoring all the usual problems that will happen again due to a warmer climate (sea level rise, desertification etc), there are some novel ones. There will be no time for ecosystems and societies to adapt to different agricultural conditions, leading to widespread ecosystem and crop failures, cascading down to every aspect of human life.