Well, they don't make any mention of your being a male character either, and the game trailer features shots where you're the female character, but I get what you mean.
The creator and devs of the game are genuinely some of the most sex positive people on the planet. While I can't speak directly on their behalf, I've followed this game since its very beginning and believe they broadly share a worldview that queerness shouldn't be advertised as a feature, it should simply be.
Like, sex and sexuality aren't inherently heteronormative, so it's arguably more notable when games ignore reality to make that the default.
For better or worse, queerness exists in House Party as it does in real life: as part of the base experience.
