Think of it like this. I am British and Scandinavians in Sweden and Norway are both white. We are both Germanic peoples who as populations may have similar traints developed that are 'characteristic' to our distinct populations, however we are all just Germanic Caucasians.
Similarly, High Elves and Snow Elves are nothing but two different cultures and populations but of the same race. The wiki was edited by Jax, a snow elf, and he has changed things that may not be accurate or allowed. The wiki is open to edit and may be changed by anyone who requests wiki access.
I could right now, considering I have wiki access, go say that Snow Elves are prone to epilepsy, or just declare them a subrace without permission from the lore team, does not make it lore correct or allowed.
PS.
Them being slightly able to live in cold environments is more something you would adopt over time as a persona as your body finds it more prudent to produce low temperature enzymes for its actions. I would doubt they are anything lower than 1 or 2 degrees Celsius cooler in core temperature, but they may be less likely to blush and turn red, exposing their blood to cool close to the surface.
However, this would presumably make them quite lethargic.