I increasingly feel like terms like “literal”, “mythical”, “harmony”, and “reconcile” are mostly pointless. What does it mean to “reconcile Genesis with science” as @Patrick put it? Or take Biologo’s mission statement. What does it mean for there to be “harmony between science and biblical faith”? These terms are loaded and subjective.
A literal reading of Genesis doesn’t actually mean literal. There are translations, figure of speech, etc. that mean we have to actually interpret the text. How about “reconcile” and “harmony”? Does that mean that everything the Bible says can be backed up with scientific data? Does that mean there are no inconsistencies whatsoever between the ancient text and early 21st century science? I doubt that’s what most people mean when they affirm it.
So I think the point of GAE is to expand the options for a group of people who want to affirm both that science is an excellent way of knowing things about the world and the Bible is an authoritative written revelation from God. In that way I think it can appeal to all the Christian “camps” that have developed around the origins of the universe, the earth, and us (YEC/OEC/EC/TE).
GAE seems to me to essentially set up a hypothesis formed from asking, if I look at what the scientific community tells us about where we came from, and I look at what the Bible says about where we came from, is there reason to believe that both could be accounting for and describing the same reality? In other words, are both science and Genesis describing the same thing, but with different tools, language, and concerns? Then the GAE model as @swamidass has laid out goes about exploring that question from a traditional doctrinal perspective. I think there is broad appeal there, certainly for Christians, but perhaps also for non-Christians as well even if it’s just to enable them to understand and discover common ground.
I think a significant number of people who would describe themselves as YEC would be open to GAE as it does relieve some of the theological tension.
I think a significant number of people who would describe themselves as EC/TE would be open to GAE, not because they believe a recent historical Adam & Eve are required but it’s certainly a helpful model when working with more conservative Christian communities.
I think the biggest appeal would be for OEC, who seem to be more open to mainstream science, but are concerned about the ramifications/implications of human evolution.
In the end, I believe it’s important that the broader Christian community see GAE as a viable option, even if they don’t think it’s necessarily the correct option. To put it bluntly, I’d love to see YEC parents and grandparents being able to have fruitful conversations with their EC/TE college students. That isn’t really happening right now because the trust-gap between YEC and EC/TE is often too high.