Back in the 90s some comic companies actually did stuff like this.
Not full-on nudity, but I remember all those old Lady Death lingerie issues, that were nothing but full-page pin-up pics of her and other characters.
I feel like Marvel has at least done bikini/swimsuit books too, but I may be wrong.
PSM Magazine used to do swimsuit issues of video game girls.
Besides, considering how much people lose their SHIT on tumblr these days over an ever-so-slightly suggestive pose, or if a female character isn't covered from head to toe like a fucking nun, it really isn't too surprising they don't do this stuff, sadly.