You doubt the normal win ratio would be 50/50? When the game tries to match people with similar skill? I'd like to see your statistical explaination behind that. In slow and small words if you like.
As requested, small words slowly.
There are two possible results to a game of CoH2. Win, or Loss. Simple, easy. Does not mean the probability of each is 50/50. Does not mean the average trend of all players on a particular side is 50/50.
Of course, for every game played there has to be a winner and a loser, but I'm making the assumption you're not assuming I somehow don't realise that. Right... right? We split the win ratios against Allies and Axis and examine each separately because the data is otherwise utterly meaningless
Examples of things which will skew results:
State of Balance in the game.
Americans in 1v1, for example, are considered very, very powerful, whilst Ost is often marked as the biggest struggle. Win ratios for Americans and Allies in 1v1 will likely be skewed in respect to this.
Automatch mechanics and player weights
A long standing abundance of axis players in the queue against a minority allies and a generally imperfect automatch system mean that we're not, in fact, all guaranteed to face off against people of equal skill. Nor does it mean we will
average people of equal skill. Just because more games are being made does not mean that the system in place will trend towards a match of people against their opposite number as a net average.
There's two. Want more?