>>68452509Honestly, I don't see those often. They exist, kinda. But they just get completely buried under tons and tons of yuri (and a bit of yaoi).
I do, however, remember EbiMaru being pretty popular a few years ago, getting lots of clips and comics
https://www.youtube.com/watch?v=PwWPRZ_R6ucIt did die out quite a bit, but you can still see fanart popping up once in a while.
I won't rule out "cucking" as the main reason of hetero not being popular, but I wonder if this all there is to it.