Just because she oversees operations, it doesn't make her a mentor.
Her role is nothing more than Kat Manx and Miss Fairweather. Shes a tech person. She gives the rangers information on their arsenal that she designs. What makes her any different?
She doesn't do what the other mentors of the past have done and teach the rangers lessons; impart wisdom to them etc
Zordon, Mitchell, Shayla, Sensei, Tommy, Cruger, Udonna, Hartford/Spenser, and R.J. all did that.
Strangely enough, it seems to be the rangers (so far) trying to teach Dr K lessons on humanity:
Ex: "Ranger Red" where Scott disobey's K's orders and orders the team to rescue the civilians in danger.