The US wins the war in 1945. Midway was in no way relevant to the overall outcome of the war. The sheer industrial discrepancy between the US and Japan would allow the US to make good any loses they suffered in the battle of Midway, and the island itself does nothing for the Japanese position. This is leaving aside the question if the Japanese even could have taken the island in an opposed landing. As far as I know, the Japanese only managed to carry one opposed landing against the US during the entire war - on the second attempt, at Wake Island.
So, if we were perfectly historical, getting into a war with the US as Japan would require a reload because you just lost the game.
Germany loses. Taking Stalingrad still means they have a gigantic frontline which - in that moment - is hanging in the air in large stretches. They have to garrison an enormous amount of territory full of people who don't like them. The amount of actual production they get out of the occupied territories is appalling. The US is only going to ramp up production in virtually untouchable factories and will continue to supply the Soviet Union with ever increasing amounts of material. Taking the Suez makes the allied position in the Mediterranean untenable - for the moment. However, the Axis forces are at the absolute edge of their logistical capabilities, and taking the Suez will not fundamentally change that. It also does not fundamentally get the Allies any closer to defeat. At best, it keeps Italy in the war long term instead of exposing the weak underbelly of the continent. In many ways, an Axis victory in North Africa only prevents a defeat, not create a victory. Neither scenario allows for an Axis victory.
That is the fundamental crux of the game: the material reasons for the axis defeat are so utterly overwhelming that it would be impossible for a realistic, historic game to have any other outcome but an axis defeat. That means there is no actual strategy involved, the axis player can merely delay the inevitable, the allied player would need to make an active effort to lose the war. That is not the game we are making. Germany being able to win the war is one core pillar of the game experience, and that means it will have to be able to successfully navally invade at least Britain and occupy enough of the Soviet Union to force their surrender, both utterly ludicrous notions for anyone who actually understand the logistical requirements of those undertakings. So at its core, the game already requires us to completely abandon historical accuracy insofar as outcomes are concerned.
The reason why we have this as a core pillar of the HoI experience is because it makes the game a Grand Strategy Game. It requires both sides to use strategic decision making, because there is a real chance for victory and defeat depending on your choices and decisions. We also believe that having different strategic scenarios - with different constellations of alliances and ideally fronts in different parts of the world - dramatically increases replayability. For that, we have to sort of abandon the starting position of 1936 to present a new challenge. We still think that the historical setup is fun and a core part of the experience - can you lead your country through the chaos? - but all hard evidence shows that a large percentage of our playerbase likes the ahistoric scenarios.
It should be noted that the ahistoric scenarios are usually a lot easier to make simply because you aren't constrained by history that needs to be represented through game mechanics.