Advertisers are notoriously poor at proving ROI, so you could be right in your assessment of his worth to them. Anyway, if putting a ball through a hoop was a bankable skill, this guy would be a billionaire: https://www.youtube.com/watch?v=oG_DQXEK764
Case in point is that worth of Mayers might depend on far too many factors which we cant comprehend and we must not judge her.