Old-school JWs were readers. Of course, what they were reading was nonsense, but it was deep nonsense. It took some time to digest all the material they had to read. These people were more apt to give a courageous defense of their doctrines.
New-school JWs are not readers. Since 2000, the publications have been more fluffy and lite as time goes by. The public Watchtower and Awake are pretty flimsy. Modern JWs cannot defend their beliefs and the go-to strategy is to run.
A picture is worth a thousand words, as the saying goes. A multimedia presentation is more effective. Much of the content of Dub TV is emotional. The music, especially, is designed to tug at heartstrings. It could be that this Dub TV will be effective at keeping hardcore JWs in.