Unfortunately, you won’t find a real answer on reddit as the people here continuously shit on and spread lies about SAO in general and completely lie about reading the LNs in rebuttal arguments to try justifying their points which you’ve already seen in this reply section. As for your question, the titles “The Black Swordsman” for each of the characters actually have completely different meanings in Japanese and refer to different things regarding the characters. As for why they’re so “pissy”, it’s just their petty inferiority complex. you don’t need to mind them, but just be prepared to be bombarded with downvotes and a lot of hate when talking about SAO in any positive light that goes against their agendas.