"Lying" seems a bit harsh and unwarranted ? In my experience your figures are quite pessimistic unless you're talking about doing a constant 70mph+ (indicated 77) on the motorway for the entire journey or you have a lead foot.Whomever told you that you'd get 60-80miles in Winter was lying to you, or they live in the south of France. In the UK expect no more than 60miles in winter if you don't like freezing. @80 in Summer and @60 in winter is pretty accurate in normal driving. If you drive slow and steady you'll get more in Summer, but not so much in winter.
Quoting an EV's range based solely on worst case scenario fast motorway driving is about as unfair as quoting the MPG of an ICE based solely on motorway speeds instead of using a "combined" figure as is usually done.
My daily commute is 37 miles - half that is in 30/40 zones, the other half on the motorway at 70mph. Today the battery went from 82% at departure down to 46% getting home - so 37 miles done with 36% of the battery used, that extrapolates out to 102 miles range. Ambient temperature is around 15-17 degrees. SoH 88.5%.
On the very first long trip I did in the Leaf after buying it last year I managed 102 miles with 11% remaining - the vast majority of that was on the motorway albeit some of it was at 60mph instead of 70 due to congestion. (M8 from Glasgow to Edinburgh) That particular trip had three adults, a child and a full boot of luggage and it was a very hot day that needed the A/C on.
For mixed local/motorway driving I am actually getting about 100 miles real world range in the summer and in winter 0-4C it was typically 80 miles. (Battery discharged from 100% to 55% for the same 37 miles - which extrapolates to 82 miles range) The very worst I ever saw with -8C weather and the heater turned up to about 23C was 70 miles, but those were extreme conditions.
A daily commute has the added penalty in the winter that you have to warm the car up twice - once potentially with plugged in preheating but the return trip is heating the car purely from battery. A single long trip would give a bit more range in winter than two shorter ones.
If you put you foot down and do well over the motorway speed limit the entire journey then yeah, your figures are more accurate.