In versions 1.19.10 and above, when attacked, the wither will break a 4x6x4 area of blocks around it, then a 20gt (1 second) cool down will start until it can break the area of blocks again. In all prior versions that the wither has had the capability to break blocks in this way, the cool down was 10gt (0.5 seconds). I think that most of the community that use this functionality of the wither would like to have the cooldown reverted to 0.5 seconds