I think Xenogears was rather trying to stay true to the form and push the boundaries to see how far it can really go, rather than self-awaredly critique it. Hundreds of characters, thousands of years of back story, layers of betrayals, puppets of other puppets, Xenogears had it all and tried to approach it with an erudite seriousness, like, if your going to make RPGs, you better bring your A game. But with the visuals, the music and the storytelling, it was very much the embodiment of everything PlayStation JRPGs were going for in the post-SNES era.