We've had over 300 posts arguing about less than .01% of the mod. Because WOTC didn't explicitly detail out something that most groups are going to not notice, ignore or the DM is going to have to spend 5 minutes adjusting to suit their idea of realistic. The posters complaining base their judgement on modern standards without accepting that some regions have had nearly total crop failures in the past yet people survived.
I don't expect reality simulation from anything D&D, I don't see why anyone would expect it now. What were they supposed to do? Hire a group of climatologists, historians, experts in sub arctic flora and fauna to write a scientifically accurate paper? Because honestly I have no clue what changes to the climate would have to be made to get the level of desperation implied by the mod. While I haven't read the mod my take is that if things don't change, the north is looking at a near extinction level event for surface dwellers. It has to be bad. How bad? Heck if I know.
If you think the description is too harsh (or not harsh enough) change the 3 sentences involved. For example it's spring of the 2nd year and it's getting worse, not better. They're starting to get desperate. While they had barely enough resources to make it through the past year they won't survive another. Tweak the temperatures so the lowest values only happen now and then, adjust the con DC to whatever value makes sense. Done.
If there are major problems with the structure of the rest of the mod, fine. I haven't read the mod I have no clue. But this? Meh.