How have digital technologies changed the skillset needed to become a creative practitioner?
Almost any form of creative work now has some sort of digital integration, even in the art and crafts world. New skills are a necessity in other areas such as photography as in the present you will be working with digital cameras and then using post processing software to manipulate your images. Using a digital camera is imperative as it will vastly increase the efficiency of your workflow (If you have the skills to use it sufficiently). Anyone who has been in the photography field since the time of film cameras and the dark room will have to pick up these new skills to stay relevant, however to say it is impossible to practice in your trade with older formats is wrong because using nostalgia can be a very marketable tool.
Not all skills are completely different and many are transferable to other production methods. You may consider digital art as a part of this category because it it is very possible to purchase a drawing tablet that means you can continue to draw relatively naturally, but transfer it to the screen instead. Additionally, many programs, such as Photoshop, contain tools that replicate real world techniques. Transferring your own skills and adapting them to a new medium is a skillset in itself.
On the marketing side I think that it is incredibly important to keep up to date with the most relevant marketing technologies. It is much more convenient to use the internet as an advertising tool because it can reach so many people due to its widespread use and personability. Self promotion, and having the necessary skills to self promote, is important because of the pure saturation of the web space, filled with other practitioners.