IT'S THE SAME FUCKING GODDAMN ENDING AGAIN. FUCK THIS I AM NOT READING THE ENDING
Ignoring that we have two chapters until the ending? Looking through the last few chapters of
Dagashi Kashi, you have to really reduce the ending of the aforementioned to something trivial before you can say that
could even be the "exact same ending".
No idea about the Japanese, but I did look at the comments in a Korean site that uploads the raws earlier and it's 1:1 what's going on here.
Koreans are a whole different ballpark... I don't even mean to charge you with an unfair conflation of the Japanese and the Koreans (it is, but I don't want to rag on you about it)-- I really do just mean that you're engaging with a significantly different culture (to say nothing of their different comic book culture, based on my not-too-meager experiences with manhwa).
Something not being to your tastes doesn't mean it's bad. "Unsatisfying" endings are often the most true to life. Not everything works out or gets cleanly resolved. People can be wrong and make mistakes. Some people value those endings.
Authors ought to write for themselves, not their audience. Tattling to an editor because a story personally upsets you is low character, childish behavior. Frankly speaking, it's pathetic. If you can't handle it, if you don't like it, then drop the story and don't buy any merch. It obviously wasn't for you - move on with your life. Don't be vindictive that a story wasn't what you wanted it to be, and try to shackle an author's voice. It's Kotoyama's story to tell, and if nobody wants to hear it, she'll have no audience. If people do want to hear it, she will have an audience. Whining won't change that.
I think the most important thing, more than being "true to life", is "having a point". It remains to be seen what the ending even
is, let alone whether it'll have a point that doesn't manage waste too much of the narrative. I'd be baffled if the ambiguities that Kotoyama herself drew attention to weren't addressed explicitly, because it would come off as using that plot device to the utmost to force this kind of separation despite those deliberate ambiguities (even if it makes sense that they wouldn't want to chance it).
Even then, where we're at right now is an
adequate payoff inasmuch as it doesn't waste the narrative preceding it. Kou is a drastically changed person from the first chapter of this narrative
because of the experiences he had since then, whether or not him and Nazuna get to [hug] and play video games for the rest of their lives (or un-lives). He learned how to connect with and empathize with others and society, and learned the value of doing so-- that was his problem presented at the beginning of the narrative. The vehicle of that learning happened to be his romance with Nazuna.
I'm inclined to think that the author and their steady audience owe the other their charity, when it comes to understanding. The author knows more about the innards of the work than their audience, and the audience is there to see what is ultimately the direct product of the author. As the kids say, they should "let [the author] cook", especially so that they can make the most out of their own investment in the work instead of just declaring that they wasted their time. Feedback is something to be listened to cautiously but intently rather than fully and blindly, not least of all because the average reader (of any fiction, I reckon) doesn't know how to adequately articulate their desires and criticisms on account of being unfamiliar with story crafting.
However, the audience is also spending time and money for the author's sake, so they can continue producing whatever it is they like enough to spend time and money on. The author can't forget that, and my understanding is that the editor is supposed to filter, interpret, and harmonize feedback with the author's intent in order to point the author in a direction that simultaneously maximizes as much as possible 1) the appeal of the work to its audience as well as 2) the author's intentions.
Kotoyama being able to "write for herself" comes off as a privilege she earned from well-executing something that happened to significantly appeal to both her and her target audience. And if you've stuck around for this long, I think it's more worth it to attempt to understand why the mangaka would wind down the story like this.