concrete powder, sand and gravel drops in use with pistons

Following problem. I built a castle gate with piston and black concrete powder that is activated with a button. When I press the button the pistons go down and the black concrete powder went down with the pistons without dropping. After the update to version 1.16.1, the black concrete powder suddenly drops when the pistons moves down. Is it on purpose? If so, please explain why. If not, please fix the bug as soon as possible, because many of my entrances and exits are protected against monsters with such a gate. Because they look much nicer than a clumsy redstone iron door.