Lmao isn't your entire downplay of Loki and Haralds about the fact that you think they cant deal with BG and Flaming Bagua or whatever its called?
Anyway, Loki didn't lose in a 1v1 fight with Shanks, which is why he calls him a coward. It's pretty simple, the entire arc is full of false premises being shown to be wrong when taken too literally, like Garp and Roger teaming up to "take down" Rocks