I'm no expert by any standard. I enjoy some backstory. There are definitely some things that can be implied and others that can be brought into the story through a brief explanation. I also struggle with when things are appropriate. I'm working on writing a series that tells the same timeline through the distinctly different experiences of three characters. The constant challenge is covering interactions with other characters already written about quickly.

For example, I will reuse dialogue to sync time between the character's experiences. It is useful for both backstory and character development to insert language that indicates their personal take on the conversation.

I hope I've not further muddied the waters with my answer.

Side note: I read erotica for the same reason people used to watch Cinemax late at night. It wasn't fully porn, and it certainly wasn't a blockbuster production. It was often real people doing realistic things in exaggerated situations. Sometimes softcore porn, though. 😐