I’ve mentioned before that there’s been a sea-change in Dynasty commenting fairly recently concerning, let’s say, “possible romantic triads” in yuri stories.
For quite a while, the appearance of any third-party character (or even the Love Triangle
tag itself) would immediately attract a bunch of negative comments about how toxic, overused, or otherwise distasteful love triangles were, and much discussion would ensue about which pair of characters should end up together and which third wheel should be disposed of.
Then, slowly at first and much more often recently, the same narrative configuration has sparked comments from readers who are avidly hoping for a polyamorous outcome. The main difference between what happens with the poly hopefuls and previous garden-variety shipping is that discussion threads often spin off into debates about peoples’ attitudes about real-life polyamory, even when the story itself gives off few signals that a poly outcome is even remotely possible.
In general, my impression is that the manga industry in general lags well behind those readers who are seeking, for whatever reasons, polyamorous yuri stories, and given the history of the love-triangle trope in romance narratives, that situation is likely to prevail for quite some time.
Anyone is free to express their story-outcome preferences at any time, of course, but I think it’s at best unproductive when discussions devolve into matters that are far removed from the story that is actually on the page.