>>4038713Matsui does like straight, or at least mostly straight, traps. But I can all but guarantee that the no homo is a WSJ policy, not a Matsui one. He seemingly snuck in Myozurumaru giving Takauji a blowjob. And the part where Takauji offers for Tokiyuki to become his serving boy has extremely obvious implications for anyone in the know.
Myozuru getting with girls is just, as the other anon said, an accurate representation of shudo relationships. Both the man and the boy were still allowed to sleep around with women. And I think for Myozuru specifically Matsui wanted to throw him a bone after dumping on him as hard as he did. Basically saying "he was actually a much desired, virile Chad and not just a loser".
Like it or not, many people see homosexuality as inherently effeminate, and effeminacy in boys and men as bad. A lot of the bara and Tom of Finland type hypermasculinity is rooted in trying to repudiate this assumption. But Matsui likes boys who do look girly. So he instead tends to go with the other common way of reassuring audiences that a boy is actually cool and manly. He makes them desired by women.