Think people were expecting some big melodramatic ending, or some kind of bowtie to neatly wrap every loose end together, but that's not what this manga was about since the beginning.
Rather, it was more like a reflection of reality, mirroring the Sisyphean journey of life as well as the complexity of the relationships that are weaved through it.
All things considered, I think the author did a great job tackling this kind of societal taboo while also highlighting some of the inherently toxic aspects of urban culture.