Fictional characters aren't real??? Writing nsfw content for a character that's on television is not different than writing nsfw content for a character (18+ bc the sheer amount of nsfw content for underage characters is beyond repulsive) that doesn't have an actor attributed to them. Book characters, for example. Authors may give character descriptions, and people may do fancasts, but ultimately, these characters are fictional. You are not harming or violating consent based off a fictional character because alas! The character is fictional.
Rpf is nowhere near journalism?? Firstly, you have those trash magazines that make up flagrantly glade info and gossip for money. Essentially, the original click-bait. And guess what, libel is an offense that can have legal action taken against the magazine by the person the magazine is spreading misinformation about. On top of which, when news outlets (ones that are reputable and wish to avoid legal actions) either take a misstep, misprint, or for lack of a better term, fuck up in the reporting, they often will make moves to fix that. And typically, consent is involved. Consent is key. Rpf, or real person fanfic, has a very distinct lack of consent. Even if the content is fluffy or sweet or soft, if the person the fic is about did not give EXPLICIT consent (and almost every time, this person did not), then the rpf is a violation of consent. Actors and people you admire that you write about that are real did not consent to have you write about them. Thus rpf is not okay. There is a very distinct difference between fictional and real life, especially when it comes to consent and stories written. Hopefully this made sense and wasn't repeating what was said!
Tl;dr: journalism is not rpf, rpf has a distinct lack of consent, fictional character fanfic is okay because the characters are fictional.