Sure, but tutoring involves learning and improving the skills at hand. Meritocracy doesn't mean equal opportunity, it means candidates are evaluated equally without regard to superficial characteristics like appearance. A meritocratic test will award higher scores to test takers that can read and analyze passages faster and solve math problems more reliability. Whether those test takers possess that ability innately, or built up that ability through loads of studying doesn't alter the fact that it's a meritocratic test.

Of course candidates that study more have an advantage. But that doesn't make it non-meritocratic. That'd be like saying a marathon isn't meritocratic because some people spend more time training.