One might ask, if (as Rhode indicates here) they anticipate many (most) guests won't have much familiarity with Avatar, what is the advantage of basing the land off a media franchise at all? The logic behind synergy is that each iteration of the franchise reinforces all the others. That doesn't seem likely here, for reasons the article makes clear. To go a step further, the logic behind transmedia storytelling, the accelerated form of synergy that drives the modern entertainment industry, is that each iteration of the franchise serves as a serialized installment that advances the overall story in a unique way, thereby coercing fans to invest in every product or miss out on the story. Avatar Land is set after the planned 4 movies and was designed with little or no knowledge of what they contain, thereby making it impossible for the land to tie into those stories in a meaningful way. In fact, this was likely the primary motivation in setting the land in the distant future - it doesn't tie Cameron's hands in any way as he plans the next installments.
In short, Disney will glean the disadvantages of synergy - lack of full control of the property, tying their investment's fortunes to unproduced media (what becomes of the land if the Avatar sequels come out and are cultural laughingstocks? Or what if the mercurial Cameron decides that the last Avatar film ends with Pandora exploding?) - with none of the advantages.
If you design your franchised land with the assumption that guests don't know the franchise, why not just design a new land?
