You think Divergent is more accessible and had a bigger cultural impact than the likes of Death Note, Dragon Ball, Attack on Titan or Fullmetal Alchemist? Realy?
Of course not, that's why I compared anime and YA broadly. The most popular YA series: Harry Potter, Hunger Games and Twilight absolutely out impact all of those put together, even though they are some of if not THE biggest Anime franchises right now. My point is not that anime is not worth adapting, but that YA, being an all around more impactful and popular niche in the west cannot be used as a comparison or benchmark. Case in point, you can ask any person Gen X down to teens about Dragonball and there's some recognition, but you can ask anyone ALIVE about Harry Potter, and there'll be some recognition.
There aren't? Cause pretty much everyone knows what Dragon Ball is, even without having to be a fan of anime. You might ask a person in his/her 20s who's not a fan of anime if he/she watched Dragon ball during their childhood, and most people are probably going to say "Yes". And why is it that an anime is always considered niche, but an american cartoon like He-Man or Transformers aren't? Because they're japanese? Because had some of these stories been done by americans, i doubt people would be here discussing how niche they were. I never see anyone in the He-Man live-action thread questioning that franchise's popularity for a live-action film, even though i doubt it's as popular worldwide as the likes of Dragon Ball or Sailor Moon. Anime/ manga might be a niche, but only in the same sense the fantasy genre and superhero comic books are niche, in that some of these stories can be major cultural phenomenons, like Lord of the Rings and Spider-Man were.
Keep in mind that i'm not saying all of these properties should be adapted, i'm just arguing for their impact and how it makes financial sense to invest in them.
Anime is considered more niche because it is counter culture, so yes, it literally is just because it's Japanese, because access to it involves immersion in Japanese culture and language, and so yes, if they were done by Americans, not only would many of the stories be materially different, but, as you say, they would not be considered as niche.
And while it does make financial sense to invest in them to a lesser degree than YA properties, twist is that they require so much MORE financial investment than Western stuff aimed at a similar age group (which is part of YA pops up in the first place). The kind of fight scene that ends Twilight is the kind of fight scene that *starts* Naruto.
You answer that question right in the next paragraph...
But did it fail just because it was weird? It didn't have anything to do with the fact that it's didn't have any stars or brandable names in it? I mean, you actualy want to compare how many people know what Scott Pilgrim is in comparison with Naruto? Nevermind the fact that Naruto has already sold 200 million of copies worldwide (Scott Pilgrim's major accomplishment in 2010 was having 1 million copies in print) and that a large percentage of Naruto's fans don't even buy the manga volumes, just watch the anime.
A lot of these manga/ anime adaptations could lead into gigantic film franchises, they just need to be adapted by people who respect the spirit of the stories and know how to make a good movie. Just like the superhero genre was before this current string of successful adaptations, that's not happening. And just like a lot of people now think manga adaptations aren't possible and that their properties are too much of a niche, people also used to think that with superhero films.
It being 'weird' influences its ability to attract stars and brandable names, as does its focus on young people, eliminating the vast majority of potential brandable names, something that is also true of the animes it draws so much influence from.
And yes, clearly anime is successful worldwide, no one's questioning that, or that Naruto is more successful than Scott Pilgrim. The point is that anime presents difficulties in accessibility and cost that make adapting it uniquely difficult.
This is not unlike the challenges that comic book adaptations experienced 20-30 years ago, only the very biggest characters had any chance, and the ones that were done paled, deeply, in comparison to their comic book glory. Only after decades of development of a mainstream audience and increases in technology and filmmaking techniques that could accommodate comic book action did they begin to have their heydey, which we are now in the middle of.
Western adaptations of anime need a similar maturity, and no singular talent can make it happen. No singular talent will be able to, no matter how passionate and skilled, create a bankable star that can play Naruto, nor will they be able to single handedly figure out how to take all the glory of Naruto and do it on a 75M budget.
I'd love to be proved wrong, but there's just hurdles here that don't apply to YA or superhero films.
Now, all that said, this is mostly about Shonen Anime. There's absolutely nothing stopping an adaptation of Fruits Basket or even Melancholy of Haruhi Suzumiya from being just as awesome on the kind of budgets people are likely to recoup from anime adaptations.