some games have "sexual content" and or "nudity" but are not focused in pornographic content, or are "sexual relation simulators". the closest category currently available is "hentai" which usually means "anime style porn".

some horror games or for "mature" audience have nudity, but not "sexual content"; some games like those in the gta series, often include small features or minigames that may have sexual themes, which may or not include partial nudity (usually they dont feature porn-style explicit content, but similar very toned down content).

the closest thing steam had was the "nsfw" tag. i think having the word "porn" so devs that do focus in that content, can properly tag their games, and then users that may want to hide those options, or focus in the, are able to do so with filters.

since the removal of the "nsfw" tag, many games that i dont care about, are suggested as options rather than things i find more interesting to look or search, which sometimes, as i expressed above, may include the "sexual content" and or "nudity", but arent "porn" or "hentai".