As cool as giant robots are in fantasy, I'm a big believer that as war machines equally sized tanks are more practical. I'd take a Bolo (Keith Laumer) to a Gundam for example.
That said, given how popular Gundam is in Japan and it's problems, I suppose it has value as a national rallying point if nothing else. Something they can show off in a "we dreamed it, we made it happen" sense, albiet I think anyone who isn't Japanese or a huge nerd is going to have mixed feelings about it.
I'm more interested in Japan's smaller scale robots in a practical sense, not just because of the "sex droid" stuff people have talked about (lol), but because over time I can actually see practical applications for that technology, where a human shape war robot (even if it can fly) just isn't a practical design, especially right now.
I've read some science fiction justifying human-form vehicles in terms of an EA enviroment, argueing that the torso (piloting compartment), sensor cluster (head), and manipulators/EVA arms (arms) all comes from practical requirements, and with aerodynamics not being a big deal in a space envorment there is no reason to not stylize it as a human as opposed to a pod if that floats your boat. That said, why you would want legs on the bloody thing is a big question, especially seeing as the only justification for it is it not going into an atmospheric enviroment to begin with.
No jealousy there or anything, I just think the idea is dumb. Sort of like the AT ATs in Star Wars, I find the idea of a tank you can trip kind of absurd. Had the Empire just put treads, or better yet a gravitic lift system on the things they probably would have done
much better.