I believe that nature shows have the ability to connect people to part of nature they may never get to experience personally. There is a large variety of nature shows that cover all different parts of the world, including some very remote locations. These remote locations are often times inaccessible to the average person and nature shows bring these parts of the world to the average person.
There will always be people who are not going to connect with nature, but I believe those that find nature shows interesting and of value, generally watch them with the intent to explore further. Therefore I would say it is safe to assume that these shows are more likely to connect people to nature.
I think many of the nature television programs showcase animals and plants that are likely not available in that persons local area, I think most people who watch these shows are often outside exploring their local nature and like to expand their knowledge by watching nature shows on the television.
Nature shows provide viewers with views and perspectives of animals and places that they might otherwise never have the chance to experience. The cost of seeing some of the world's more exotic places or observing wildlife firsthand is too exorbitant for many people. Nature shows give them the opportunity to develop a respect and understanding for things in nature despite limitations.
Of course if all someone does is watch nature shows indoors then that is sad. But some people can not get out and other people will watch a show like this and decide to make a trip there themselves. So seeing programs on nature can stimulate the appetite to see more of nature.