That’s her schtick and part of the act - no matter how boisterous Prima would become to win her attention, she would act totally laconic and unimpressed, roll her eyes, deadpan, etc., but sing she can, man.
I can’t document it, but sure looks like the premise for Sonny & Cher, who were tame in comparison.
I have some of their 50’s albums - my parents used to see them in New Orleans
Glad to hip you to something old & new
Enjoy
I always thought Sonny Bono copped their act. The only difference was that Prima and Smith had talent.