Bookmatching isnt perfect becasue one has to cut, sand, and plane the veneer down. As such, the two sides diverge from the point at which they would match. Look at a piece of wood. Is the grain exactly the same on one side as the other? No. Thats why bookmatching isnt perfect.
My theory is that a guitar is meant to be viewed from a distance. Say 4 ft at least. At that distance, you really cant tell.
Figured woods have bvery active grain, so it may seem like they match less. Something like cherry with fine grain may be less noticeable.