That's a ridiculous statement. Sarah has a sterling record of accomplishment as a Governor, and in many other public service positions, both elected and appointed.
The fact that she's been out of elective office for four years has absolutely no bearing on her proven skills as an executive.
As far as gravitas is concerned, let's not forget that her endorsement helped the almost unknown Ted Cruz defeat a sitting Lt. Governor in his race for the U.S. Senate last year.