There is a difference between balance and symmetry. This version of Axis and Allies is intended to be two very different forces against one another, with diverse choices and unequal assets. Chess is a fully balanced and symmetrical game (its fair balanced because white gets +1 more move and black gets +1 more piece of information and its symmetrical because you get to have the exact same assets.)
This type of “opposing forces” has become more and more popular. G42 is a great example of a more balanced and symmetrical set up than G40. Xwing starfighter has completely imbalanced sides with dissimilar assets, as do many 21century TTWGs
However, there is a point that we find that asymmetrical and imbalanced forces imply a kind of bias or advantage. This is very hard to argue in absolute terms since player skill, luck, and plain errors can bias the outcome of any survey of wins/v/losses.
I am not fully convinced that the game is biased towards one side or the other, over the complete game (14-16 turns). 95% of games are ended by time or patience running out and one side capitulating, this should be a tremendous sign that we are not really assessing the games objective bias or balance but rather telegraphing our opinions and unsupported conclusions onto it.
The more effective analysis is that a combination of luck and strong play will reduce the game to a specific contest (eg one battle for Moscow or pacific naval dominance), a contest that will be won by small decisions leading up to it. All of the other side stuff (battle for Africa etc.) is essentially meaningless and distracting. I am not convinced by my experience that these culminating battles are entirely in the favor of one side or another, but rather that by the time we reach the crucial point we are all too clouded by exhaustion and small considerations to recognize that the outcome is largely dependent on luck and the culmination of small decisions over time.
I do agree in general that the Axis have a much clearer, cleaner path to victory and that they are more adaptable and flexible. But this does not necessarily translate into an overwhelming material advantage at the crucial point in every game, which makes me believe that the bid (while a good flexible solution) is not necessary and is a bigger bias than it intends to address.
I am open minded, and given the varying skill levels of all players and the chance for a mistake, I would rather play with diverse players or random team assignments (as a way of addressing a putative advantage), and accept that the fun is in winning (or trying to win) with a “losing” side.
Good Luck Brothers.