I feel like a lot of context is missing for those who haven't grown up in Japan or don't have knowledge of the way corporate entities work there. I'll attempt to explain some, but take what I say with a grain of salt; I've lived here a number of years now but that hardly means I know everything.
Japanese corporations operate more like conglomerates (ie: horizontal corporate entities as opposed to vertical as is more common in the west), there are exceptions, but in general competition is very low between companies and thus they tend to collaborate. The fashion companies literally hold large inter-board meetings to decide fashion trends for the year, manga/entertainment companies try not to go outside the box (this is why so many isekai are being published), and the three big banks control most of the money in the market withholding money from those who would break the mold and low interest rates for the normal person to prevent capital gains (and losses for the bank, the Nikkei hasn't been doing that well the past 20 years).
Anyway, I haven't read the Japanese source so I could be totally wrong, but I feel like there is a lot of reference to Japanese people suppressing their individuality due to many of the things listed above. You can't have individuality when the conglomerates control what can be bought and don't care about competition; thus individuality dies for the Japanese child as they age.
A good book to read that talks slightly about the lifestyle of Japanese people from childhood to adult life is The Chrysanthemum and Sword by Ruth Benedict, chapters 11 and 12. The book was written during and just after WWII, but as an educational researcher I was shocked to see how little had changed in the past 70 years. In essence freedom is slowly stripped from children as they get older.
So, NisiOisiN has written another deconstruction. But rather than a deconstruction of a genre like he did with Monogatari, or Medeka, in one chapter he has revealed a deconstruction of the entire way of life for Japan, with multiple layers. It is beautiful in many ways, and horrifying in others. To save her from a life without individuality is to kill her. To save her from a life of individuality is to kill her. To love is to kill. Yet, in an almost self aware way, it also knows that by revealing something so tragic it gives readers a way to empathize and thus fit in with the norms of Japanese society.
Sorry for the rambling, didn't have a lot of time to explain what I think it means and if things aren't coherent I'll try to come back and fix it later (not that anyone will read it or care).