Didn't they have alternate titles in english on the series page at some point? I swear it used to be that way.
Yeah, just checked, this one's got it too, but others don't. Standardize that shit, yo.
Which title is listed primarily is apparently at the discretion of whoever makes the title's page/entry or edits it thereafter. In a lot of cases it seems like when someone uploaded an English translation the title was set to English. But according to people from other series that have talked about this, it appears someone or a group of someones is manually visiting various series pages and changing the primary title to transliterated Japanese/romanji while
maybe leaving the secondary title listing as the translation.
Apparently this should be coming to an end at some point as Mangadex is planning on implementing a system that will allow the display title to be switched or controlled so that you can have translations as your primary display title. That can't come soon enough.