Haha ive answered this before so i hope you arent the same person XD.
So iirc I heard from someone in Korea explain that 'salt' or 'salty' can be used connotatively as 'angst' essentially. Kind of like how american use it to describe someone mad they say "you salty?" Like asking if theyre mad. Well koreans, at least in their writting, use it for angst or a bitter emotional state. Thats what ive heard at least. Hope that helps

Why do manhwas with 'salty' in the title tend to be so toxic, and if not toxic then it's pregnant and fled it's kind of a headache to read lol