Ok, I think you have a few misconceptions here, here are some of my thoughts:
Like you said, you can go to the official English Shonen Jump site and get the "official" English name, but you know, that's not necessarily the actual official English name all the time...Some series like Takujou no Ageha or Kuroko no Basket had an English subtitle on the Japanese prints, in these cases they were "Butterfly on Table" and "The Basketball which Kuroko Plays", I think they changed the way they called Ageha for the Jump start chapters but isn't that kinda going against the author's freedom to call his series however the hell he wants? (even if they sound really weird like Kuroko's or are plain bad translations like Ageha or Kyojin for another example)
Also, not calling Tokyo Ghoul "Tokyo Kushu" or Prison School "Kangoku Gakuen" doesn't actually go against this because in those cases even if the kanji are read the second way normally, the furigana especifically says you should read "Kushu" as "Ghoul" (Guuru) and so on, that happens a lot with many LN series too, like say Machine Doll wa Kizu Tsukanai or Seiken Tsukai no World Break, because well, the "shinigami syndrome" you mention also happens in the opposite way in Japanese people
And I don't even know why you call using these Japanese names something forced or despise their use so much, yeah sure this is an international board, but I don't see any problem on calling any particular series on whichever of its official names or an abreviation of them, I mean, I personally hate some of the official English names like say "Food Wars" (because Shokugeki is untranslatable, and I think untranslatable words are best left like that because, well, that's how foreign words get added to languages in the first place, but that's a topic for another time) but you don't see me bashing anyone who uses it, right?
Anyway, that's pretty much all I have left to say about what's been mentioned regarding this topic, and we probably should leave it alone because discussing this is as useless as discussing whether subs or dubs are better, some people like their entertainment to adapt to them and some people like to adapt to their entertainment, and I don't really think any of them is particularly better