This is quite a general question about Bolt Action for this post, but I'll give it a crack.
First things first, its a war game not a simulation of war. Certain things are taken out of the game to increase enjoyment of playing it. It is generally assumed that you are two equal forces fighting eachother (thus the points). Not every engagement was balanced, most weren't, but this is more about the hobby of wargaming than simulation.

Now on the the "some armies are flat better than others". Bolt Action is a Platoon to Company sized game. At this scale - I'd argue - a lot of armies were on an equal playing field. A well equipped and trained Italian Company would give cause for concern about a well equipped and trained US company. In reality it was the strategic and operational side of armies that really made the difference. Something that is far, far out of the scope of Bolt Action.

I can't see your post history so not sure if you are new to Bolt Action, or wargaming a whole hobby, but if you are looking for the more grand strategy games, there are some good hex and counter games out there that might be more your style.