First of all, I don't watch BL/GL so I have no idea, but let's try to think about it.
Second of all, anime is fiction, yes, there is this idea that art imitates life, obviously reality is an inspiration for anime, but I think the argument "homosexuals irl don't practice monogamy so why should they in anime" is irrelevant. All that matters is the intended experience, does it serve the goals of the show?
Ok so here's what I think. Harems/polygamy is kind of a niche genre, it's not automatically a more is better situation. I am viewing this more from a hetero perspective but fundamentally I don't think there's that much of a difference between a gay harem and a regular harem etc.
In eroge there is a similar question, is it better to have 1 heroine or a party of heroines? On the upside, more heroines means more variety, you can have like a muscle girl, a goth loli, a monster girl and a big titty onee-san all in one, the pool of available scenarios is also larger (in theory) by letting the girls play off each others character. However, Eroge are made on a budget, maybe there's only 50 CGI for the whole game, that means only 12 per character or alternatively 1 or 2 of the characters get shafted to let the rest get more development. What happens when you get really into the muscle girl character only to find out she was one of the characters that got shafted? What happens when you hate lolis and you are forced to interact with her when you would rather just talk to the muscle girl. What if you actually like all the characters but you finish the game and you are kind of like "well shit, that game was wide as an ocean and deep as a puddle, I barely got to know these girls"?
So I think it should be evident there is no right answer here, whatever you choose you are taking a risk. In my opinion, 1 on 1 relationships are the best because you get to spend more time with the characters you like (or conversely, you can quickly identify that you hate the characters and peace out), you get to deepen the bond more.
The other major concern is the dynamic differences between 1 on 1 and polyamory. One way or another you have to think about what everyone involved thinks about everyone else, it's a more complicated relationship which may be incompatible with the story the author wants to tell, e.g. let's say they want to do the whole slow burn "first love" type deal, well I guess you can still do it with 3 or more people but it won't be the same.
So yeah, I guess my main point is, I think the authors of these stories know very well polyamory is an option, it's just not an option they are interested in. |