I haven't been in this business long, but I think your horizontal axis is a bit arbitrary. I'm not sure who the skill aspect of the horizontal axis reflects on. If you're talking about the learner, then their skill set shouldn't need to increase to use an eLearning app vs a presentation. Developing eLearning may require a wider skill set, but with the tools Tom has been recommending over the last few months that I've been reading here I feel pretty sure it's possible to develop an eLearning course without ever leaving a WYSIWYG screen or touching anything a low tech person might consider scary.
Also, doesn't the development time depend on the size of the course as well as its complexity? The chart isn't clear if it's referring to eLearning courses in general, or a specific course that is developed in various ways and the comparative costs for development.
Just my 2p
-A-