Then, of course, he wasn't able to plainly accuse Hara because that could turn her in an outcast (fat girl + mocking the class "queen")
I could have believed/ understood his actions that if Ichikawa believes that the "grave threat" was just a misunderstanding, But he believes that the "grave threat" was real so sacrificing himself wouldn't have solved anything. in fact just bring trouble to himself.
Why can't he just, Stay quiet and said "wasn't me" and outcome will be more or less the same in his eyes.
- "Grave threat Real": Hara will still end up ostracizing herself. (Because taking responsibility for a deliberate action for other party doesn't stop the other party from doing it again. ie (fat girl + mocking the class "queen") is still in play.)
- "Grave threat Misunderstanding": The Misunderstanding will be fixed soon after.
The main point is that the Ichikawa, for no reason ended bringing trouble for himself for no benefit. Hence the "but this is more like switching places with someone trying to commit suicide by bus." quote from me.
Ichikawa is just being mature.
How so?
Last time I've check sacrificing for "people who don't want to be helped" (Note: Ichikawa believe that the "grave threat" was real) isn't really considered mature, In fact is considered as "childish naivety" that
just by sacrificing themselves means things will be better.
So Dunno 'bout mature, but hey. they be teens