But it's only to make a point of the fact that this game is supposed to rely so much on its narrative elements and the execution of them, yet Cage & Co. are apparently unable to avoid making the experience cringeworthy.
I didn't really find it cringeworthy. I agree that the plot has a sort of destined or teleological sense to it, which results in things maybe fitting together a little too conveniently. But I think some of that is a commentary on the limited amount of agency Jodie had in her earlier life--almost none of the game's content takes place once Jodie has full control over her situation, and almost immediately it is denied to her again.
Add to the fact that some of the characters were bordering on offensively over-used stereotypes (spiritual natives, homeless people with heart of gold, mad scientist, war-hungry military general, evil step dad, and so forth) and that not much research had gone into specific areas of some of the locations (read Erik Kain's assessment of the narrative in the game). Finally, the storytelling was simplistic and extremely heavy-handed at many points throughout the game with incredibly convenient "events" to make sure the plot moves forward in the proper, but frankly unbelievable to me, succession of events.
The evil step-dad isn't evil if you don't make choices that make it clear Jodie feels he's evil.
I think your emphasis here is that a game that portrays issues surrounding social justice should do so in a fitting way. I'm making that assumption based on what I know of your posting elsewhere and by reading between the lines of the issues you identified. I say the following as a critical and interested observer who values diversity and who has a strong draw towards issues relating to human dignity.
The homeless chapter, in my opinion, was a successful execution on a concept. If you approach it knowing that the author's obvious intent was to portray that while homeless, people are stripped of a lot of dignity, treated poorly, and forced to make a choice from a very poor set of options, I mean if you are charitable about what the author is trying to convey, I think it works. The reasoning behind the variety of homeless characters--and I agree that the way the game deals with these AFTER the homeless chapter is pretty eye-rolly--is to illustrate the sorts of people who end up homeless. People dealing with mental illness. People who lose their job and are failed by the system. People escaping abusive or harmful life-situations. I think that's pretty representative, to be honest, given the structural causes of homelessness in America. I don't recall the line you mention, and obviously the scene isn't perfect (I thought the young toughs filming their bum fighting was a over-the-top way of portraying the callous indifference and dehumanizing way people address the homeless), but I think enough of it works that I would consider it a strong execution. Additionally, it's a theme rarely if ever address in games.
I believe if you were playing an art-game made by an individual who self-identified as homeless or displaced or was drawing from personal experience, knowing the author's intent would frame that game in such a way that you would approach the material more generously than you do here.
The Navajo scene is comparatively weaker in its written content. I don't think it was minstrelly. I am white, I am not of native descent, and certainly I am open to hear someone with more direct experience responding to how they see the portrayal. I didn't see elements of "noble savage" or "white man's burden" tropes in the scene. I think the scene basically involves Jodie's coming to terms with herself--the native ancestry seemed secondary to this. While the exact symbols used, and words, and possibly even the accents probably weren't true to life (I didn't check the actors cast to know whether they cast actors of native descent or whitewashed it, this is probably an interesting thing to follow up on), I think the general thematic elements of belief in a spirit world, strong connections through ancestors, connection to and stewardship of nature, significance of hallowed ground and burial sites are common to indigenous peoples of the world. I don't think it was done in a hokey or cliche "Chief Big Bear channels the Grandfather Wolf" nonsense way.
The supernatural elements in the Navajo chapter were less strong but I'm not a big fan of supernatural content more generally and while the rest of the game's supernatural elements were considered from a basically materialist approach to reality this one scene made it a bit too, I dunno, a bit too hokey. I gave up on Phoenix Wright 2 because the traditional Japanese ghost/spirit elements were pretty dumb to me. I also feel the pacing in the Navajo chapter was a little slow.
The treatment of the ethics of war after the Somalia chapter is pretty poor, the dialogue in the plane is pretty bad. That's one of the game's weak points.