The action CLEARLY takes place in Ichiro's mind, unless you are suggesting Ichiro ACTUALLY warped there, which I don't think you are. Assuming that Godzilla is actually 'real' in this universe, it still doesn't change the fact that none of what happens is actually canon to the films, because again, it takes place in Ichiro's head.
Moreover, every interaction Ichiro has with adult regarding monsters, the adults basically dismiss it as child-like dreams on a few ocassions. If these monsters were actually real in this world, from a FILM MAKING perspective, why didn't Honda have a character blatantly say, on screen (by your criteria): "But how can you like monsters if they kill millions of people?"
The simple fact is, this movie makes the most sense as a 'real-world' film about a Godzilla fan. Whether or not that was the film makers intention, it certainly has become the modern interpretation of the film.
You are free to disagree, but I'd like to see the same evidence from your end rather than this argument about the film being consistent the movies that came before.