This concept continued until at least the late Muromachi period and the ideas that a 'betrayer is a coward' 'samurais should die with their lords' were not mainstream at the time.
この意識は少なくとも室町末期ごろまで続き、後世に言われるような「裏切りは卑怯」「主君と生死を共にするのが武士」といった考え方は当時は主流ではなかった。