One of the primary symptoms of boxwood blight are the black stem lesions or cankers. They look like streaks of black marker on the stems and branches. We believe that we do see the cankers on your boxwood in the photos.
Another main symptom is that the boxwood will drop dead leaves, usually bottom first. We do not see this.
It would be helpful if you would look for the black cankers and send close-ups of some. Assuming it is boxwood blight, which is highly contagious, you will want to remove and bag the boxwoods--including all the plant debris from them, such as fallen leaves and stems, which will carry the infection. Bag and landfill.
This disease is being spread by landscape services, home gardeners, and even comes in on newly purchased plants. Be extremely careful not to spread it by using a tool on an infected plant and then on a healthy one.
Read this closely: https://extension.umd.edu/hgic/topics/slime-flux-and-wetwood There are also helpful links for more on boxwood blight.
And, as mentioned above, you are invited to send close-ups of the black stem cankers for a more positive diagnosis.