Re: Hello, world! question
As someone who has translated that song, I remember spending an inordinate amount of time thinking about this point.
At the same time, a large portion of the song (particularly the verses and the first half of the first chorus) reads strongly like a description of the speaker's own feelings, and the only way at the time that I could reconcile that to the bridges (顔を上げて etc) was the interpretation where the speaker is talking to himself. From that mindset, the restructuring of ご自分 to "myself" feels like less of a leap, especially given the shifts in perspective that already exist in the song.
That being said, looking back, yeah, I think the correct play would be to preserve the "yourself" in a way that still allows the self-dialogue interpretation and then readjust things like the contrast with 自分 in the last chorus.
Re: Hello, world! question
I think that it's fine saying "I am the only hero", because it's more like "you're your/the only hero" (impersonal you) in Japanese.
If the rest of the song is first person and self-reflective, it'd be weird to randomly shift to the conclusion being "and so you're the hero" in the translation because it's more like it's being told to everyone including the singer. So it's a "I am the only hero", "you are the only hero", "everyone listening is the only hero" kinda thing.
So you're right strictly speaking it is "you're (impersonal you)" but think "I'm" is also okay.
Re: Hello, world! question
That's an interesting take on it, I'll have to read through the lyrics again and consider that angle.
Once I changed the meaning to "you", I felt the song took on a more interesting meaning, especially factoring the latter verses.
To me, rather than being introspective, I felt that the song was being sung (for lack of a better term) by a more or less regular person who was rescued by the "hero", and while taking a good look at that hero, realized that the hero was always in the spotlight, had nobody they could be 'protected' by, and was essentially being weighed down by the situation and responsibility, to the point of into hiding and expressing anguish over the situation. The singer realizes this, can't stand by idly any longer, and is basically trying to announce himself to the world, in an attempt to acknowledge this and take some of the burden from the hero. In the later verses, the idea seems to be that the singer is try to tell the hero that they need no longer to hide or 'play dead', because the singer has found someone they will protect (the hero), but that even with this, the singer is not looking for hero status (as the line about 'you're the only hero' is still repeated at the end of the song).
What do you think?