I don't think people are being too sensitive. Stalking is a crime, and a serious problem for many celebrities. It's perfectly normal to feel uncomfortable about it. Maybe MDL users know what a "Stalker's Guide" is, but outsiders don't.
"Bias" is less offensive because it's a well-known term throughout the entire k-pop community, and it's usually used in a positive way (favorite member of a group). As far as I know, "bias" usually isn't associated with creepy behavior. Nonetheless I probably wouldn't use "bias" in an article title.
If we can't agree that "stalker" is offensive, we can think of it from a marketing perspective. A title should make people interested in reading the article, and not be misleading.
When I see the title "Stalker's Guide", I expect an immature article, filled with unimportant personal information.
Here are some articles about famous actors that I found on google. I don't know if the articles are good, but the titles attract my attention. I think someone who wants to seriously learn about these actors will click one of these articles before they click a "Stalker's Guide".
The Last Samurai: The Life and Films of Toshiro Mifune
Japanese Cinema’s Uncommon Man: Tatsuya Nakadai’s Dissidents, Outcasts, and Shadow Warriors
Space and Transition in the Films of Setsuko Hara
The Incomparable Charisma of Chow Yun-fat
Famous Martial Arts Master Jackie Chan and His Remarkable Career