The CRT had been approved by the same person who did the review. As far as I know, the term "infinitely superior" is just one way of referring to this, but explanations of worlds with a greater number of dimensional axes can be accepted if they are quantifiably higher than worlds with fewer dimensional axes, which is the case here. And no, "exists as a fiction" is also simply another way of demonstrate this difference, anyway, there's still a difference between Feats, PIS and Outlier.
If they have created a world that is superior to another world, transcending them hierarchically and this is accepted as Tier 1 or higher, it will not just be a case of a character who is not constantly at that level that will make their whole feat as something wrong. . Especially when it can simply say that the characters are equivalent to each other, as is the case with the Dark Masters (which are directly referenced as equal to the Four Holy Beast).
About Dimensional Wall, don't ask that to me. All we know is that the Network exists between the two worlds and that it is also a multi-layered world in itself, like the Appmon which are directly referred to as "Existing on the Network that exists between the Real World and the Digital World.".
Of course, "alternative universes" do not prevent them from being higher dimensions. A "universe" being called a "higher-dimensional universe" only means that it has a greater number of dimensional axes than another universe, nothing prevents a 4-dimensional universe and a 52-dimensional universe from being called alternative universes or parallel universes, they are still universes (Even more when we start to not simply say that a universe is simply a larger volume than the 1 hubble volume of the observable universe).
And wrong, the Digital World as higher than the Real World is something that has been planned since Digimon Adventure, solidified in Adventure 02, the Dramas CD and the Novels and then reaffirmed in the Xros Wars era with the rescue of the Adventure's original concepts, used by Kakudo, by Nakashima and Habu. It's even clearer when you talk about TRI, the first 2 minutes of TRI are literally a reference to the neoplatonic emanationism concepts used by Kakudo to explain that the Digimon are in fact a soul from a World of Ideas, and these souls were detected by our world throughout history in various forms, from demons to gods or youkais, and were now viewed as virtual beings by digital-based society.
Digimon Tamers Map is only used as a reference point, although Konaka wants to treat Tamers as an isolated world (Just like every Digimon work), this is not something that Bandai/Toei does. References to the concepts covered in Digimon Tamers were used several times in other parts of the franchise, and even if Konaka did not created the originally map with this meaning, now it basically demonstrated the difference between Real, Digital and other Worlds through the Hierarchy of Worlds after the Digimon Adventure lore was reused.
Basically, we just use it because it's the only image we have of what World Hierarchy would look like, even though it was not created for that purpose, but then its concepts were used everywhere in the franchise (As much as Konaka dislike, now, the expanded universe of Digimon, this is something that we use, and so we'll try to put everything together just like what Bandai, Toei and other people that worked with Digimon does).
Of course, about each part of the franchise being isolated and not using the same concepts. This was never the plan for Digimon, as you read the initial plans you will see that they always shared the same concepts and all served to expand the same story (The one in the V-pets manuals). It was only in V-Tamer that the explanation of being parallel universes was first used and then with Digimon World 3, X and the Digimon Story games, the explanation that even the worlds, called Servers, are part of a larger Network started to be used. It is clear that many of the worlds are just different servers of the Digital World Network, all existing inside the same layer through the different layers of the Digital World (As said in the Digimon Twin Storyline).
Of course, most Digimon products were not made with this in mind so it is very easy to find inconsistencies in older products, but it is currently the explanation of how the franchise is structured and so we will use this as the most commonly used explanation today and has approval not only from its creator, Hiroyuki Kakudō, but also from Kazumasa Habu, Kenji Watanabe, Ota Kensuke and even Chiaki J. Konaka as shown in the livestreams of the new Digimon Story Games (Which was two of the games that brought these concepts back).