Will RootSkirts restrict airflow and increase humidity around the outside surface of RootMaker container and interfere with air-root-pruning?

With good watering practices, NO. Research with a number of species has not shown this to be a problem with good water management. However, if you over water continually and have water exiting drain holes after each irrigation, air-root-pruning would be reduced. However, once plants are removed from such a humid environment, any roots outside the container wall will be dehydrated and will not be a problem.