The problem is not the brick price, but extra regulations, controls that they are followed etc, plus the fact that now instead of say 10000 identical bricks for one house you need 9999 ones + one different. I simply think the priority should be more house building as people struggle to find places to live, and this measure will not help (the effect will probably be small I don't know)
It's a house, not a wall. And it's not being built by a robot. Adding the brick is inconsequential.
Go to any building site and ask a bricklayer if adding a single custom brick to the construction will stop them building the house and he'll laugh in your face.