I see he uses in photoshop auto-contrast;
as you can see auto contrast is set to cut 0,1 % of black and white.
especially with very black / very white objects like snow one would want to keep the whites not to cut them.
I never use 0,1 % cut - always set it to 0,0. I will not let "auto" decide to cut my extremes.
Also with snow photographes you often do not want to go to completely black.