I really like this chapter and the moment between the two but cannot say I feel the slightest okay with Rintaro dying his hair. The undertone here is still that dying your hair, essentially standing out from the norms, is a taboo that causes trouble for yourself and those around you. Nothing about your appearance should be a matter of "strong" or "weak" or protecting each other (so long as we aren't pushing the extremes and straight up streaking). He shouldn't have to make compromises to conform to others narrowminded beliefs about appearances.
I recently got to go to Japan for a bit and there's something seriously depressing about asking the people I met about school uniforms in anime thinking "okay this has to be dramatized; there's no way it be that bad." and then going “oh crap it’s worse.” The uniform policy is way past the point of being ridiculous and is frankly dehumanizing. I mean when a dress code for grade school students describes how long their finger nails can be, there’s a big problem. Like the very fact its assume blonde hair is dyed is indicative of systematic bias.
I can’t help but be infuriated by this situation and the fact that it’s something normal and acceptable by Japanese societal standards. I understand different cultures have different values, but a kid really should not be dealing with this much pressure just on the color of their hair. At the very least not from other students. Its insane to me that I’m watching diversity campaigns push for businesses to stop discriminating against black hair styles and embrace non traditional (well, white) hair styles, and reading a fantastically uplifting story where the main character chooses to stop dying their hair blonde (like one of the most boring and generic hair colors out there (no offense to anyone with blonde hair)) as a moment to “strength” to stand on common ground and help his girlfriend, who doesn’t care and rather appreciates where his feelings to dye his hair comes from, deal with the ideas of narrowminded high school girls who have essentially been brainwashed to be prejudiced to others appearance by an awful educational staff.
I know Rintaro himself said he doesn’t mind and wouldn’t hesitate but I know enough about dying hair (I don’t do myself though) to know it’s an active choice. If had gotten bored or it or couldn’t be bothered to deal with it he’d have stopped long ago snd let it fade (maybe not going back his natural color but definitely not keeping it completely blonde). And going back to black had to be an active choice and with the reason given of wanting to protect it just feels… wrong. This isn’t for himself or directly for any of his loved ones. Its appease outsiders and limit their negative perceptions of people he associates with which is so… disgusting (morally or ethically or I don’t really know but I hate it).