you are spot on about Yang becoming masculinized. And I also want to add a similar changed happened to Blake but in the opposite direction. Blake does have a feminine charm to her, but she's outspoken about the oppression of the faunus. She's not afraid to square up to Weiss and confront her racism head on.
But now after vol 6 she's practically meek, soft spoken, and submissive. Her fire is gone. I do believe there is bias in place, especially when making bumbleby canon. Someone has to be the man of the relationship so it had to be Yang. Blake was left to be the woman and was changed to fit the role
I think it has a lot to do with the writers thinking that making Blake feminine and softer is the best way to show she's changed rather than leaning into the traits she possesses and building on them. While Blake can be outspoken she's also more withdrawn than the other characters. She has a bit of crossover with Ren in that aspect.
I think her coming off as more standoffish slightly meek upon reunion in a way could've worked if we had the group with tension upon her arrival. If she wasn't just immediately accepted back then her being unsure of how to bridge a gap because socializing isn't her strong suit would've worked.
Honestly I think going for a more hardheaded and "stand your ground" Blake who doesn't bend would've made much more sense for how they shaped her story in canon after the events of volume 6. I think that paired up with Yang who to me always read as the smooth talker in the group could've allowed for some fun duo dynamics where Blake was more quick to jump to the point vs yang who was more willing to worm her way towards it.
But for sure they upped her feminity in weird ways. Honestly in general I haven't been the biggest fan of her writing (which has a lot to do with not liking writing for the faunus in general). I feel like the idea of "cat=feminine" has embedded itself in the writers and fandom the same way "physicality=masculine" has. And yang being taller than blake also colors opinions.







