From a program-wide perspective, I would say neither has done significnat damage. I mean, within 5 years of Westhead being fired, we were in the NCAA twice and the NIT once, some of those with Westhead's own recruits, the biggest being George Evans ( yes, I know Larranaga had to re-recruit him, but he was originally a Westhead recruit).
I believe a similar thing will happen again provided the next hire is the right one. The Hewitt years will just be a footnote
This isn't a Calipari at UMass situation with vacated NCAA wins and sanctions being placed on it. UMass hasn't been to the tournament for, what 15 years? Nor is it a UNCW situation with a president who wanted to "de-emphasize" athletics and essentially gutted the budget. Now that's how you destroy a program.
TOC made a bad hire, we are suffering for it, we will get over it.