She definitely learned a "rap" beef isn't happening.
Nicki does mess for entertainment. She probably figured this wouldn't go any further than a few shots online here and there or some subliminals thrown in a record. She's thinking it's hip hop, entertaining, giving the people a cute show etc.
Cardi kicking it up a notch and physically attacking her at an event was probably the furthest thing from Nicki's mind. I doubt she wants to be associated with that type of drama and negativity after already feeling like there's a hate train against her.
She'll probably hush her a mouth a bit now.