Historical evidence for temperatures is always ignored in the debate. Scientistis conclude that because it comes from social sciences like history, it is not worthy of regard. They are right on one aspect that it is mostly anecdotal or singular view points. But it is also clear that if you have a lot of those experiences over some time, then they shouldn’t be disregarded.
We don’t have any reliable temperature records for the pretty cold time between the 1600s and 1800s. We have tree-ring reconstructions, but they have quite an uncertainty factor. So, why not use historical descriptions of the time. And indeed those colder times were really hurtful for the people. Of course, today, we high-tech Europeans and Americans can easily deal with it, but can poorer countries say the same?
These anecdotes didn’t describe daily weather but whole seasons that brought famines and killed people en masse. People even prayed for the weather of old. I think we should recognize this as a threat. We can easily (in a warm environment) generate cold, but most technological applications are pretty sensitive towards cold environments. Hydraulic equipment works better in warmer environments, electrical components and batteries have problems with severe cold spells and we can always cool appliances. We cannot, however, always heat something automatically.
So, we should be careful what we wish for when thinking about socially engineering a specific temperature for the whole world, because nature is variable and thus it might just swing the other way.