It's not that daggerboards "make the boat point higher"; it's more that the daggerboards reduce your leeward drift dramatically when going to windward. There is no point in pointing a boat high (pinching) to windward if it is then "sliding" sideways through the water to leeward, thereby not only NOT going where it is pointed, but also going appreciably slower in the process. The daggerboards, by being approximately at the centre of lateral resistance of the hull and sail plan, and thereby acting as a pivotal point between “up and down” to the forward direction of the boat, also function to relieve pressure from off of the rudders letting them (the rudders) operate better in their designed function.