Is there such a thing as human-friendly decorating which is gender non-specific?

I strongly suspect there is. The men's setup was specifically full of masculine-coded adornments (wood, leather), and the women's setup was full of slightly feminine-coded adornments (plants, lots of light).

But I think that there's considerable overlap, and there are also environments that are considered conducive to specific kinds of activities.

For example, most people seem to like dimly lit spaces for romantic activities or "night life" (though personally I hate dimly lit places; light is cheap, why should I struggle to see things?).

OTOH most people like to work in environments with lots of natural light, the "window office," because of the cumulative effect of sunlight on mood. (Being inside and away from the sun all day wears you down. I never noticed this when I was in school because I never spent long periods of time away from the sun. Now that I work in an office it's obvious.)