She says that pirates have a moral code but Kaidou's subordinates don't and is enraged by it.
Did Big Mom just get character assassinated?
No. In WCI she had a bunch of deals with pirates that she honored... She let Pedro go. She let Luffy live when Sanji made the deal... Yada yada
Big mom is very into following deals and shit so she does see herself as some kind of moral person... Which isnt actually true... She is a lying hypocrite but in her mind she thinks she’s way more honarable than she actually is
Hence why she sees it as fine trying to kill Page one for destroying Okobore, BUT she will still try to kill Luffy, the savior of Okobore, just because Luffy made her look bad.
She is lying to herself here claiming she cares about Okobore