I don't know this specific exam, but most of these can be gamed in the sense of learning to the test. So depending on what training resources someone has available (e.g. rich parents who can afford tutors), I'd consider them only partially meritocratic.
China also bans test tutoring as a commercial service. Without a doubt people will still be able to find tutors if they're sufficiently capable, but the scale of this problem should be vastly altered by that action.
Can you learn to the test without actually learning the material?
If this is the case, then why doesn’t everyone get the top a score? The answer is, of course, that it’s not so simple, and you can’t just learn to the test.
That’s just like with sports: anyone can learn how to train himself, and anyone can improve with training, but in the end, some people will end up faster, and some people will end up slower.