i think it's more to do with the way the faction has been constructed, from my understanding and research for my elysian plot reasons, it seems that the social structure of elysia is as frost said, very racist. So much so that currently Elysia Novus (i havent heard anything about the rest of their territory i thought it was just their proclaimed homeland) is off limits to non elysians iirc and this is not because frost wants to keep players out but rather sticking to the core values of a very class based society of egotistical angelic people.
The neo caelisolan continues upholding the original virtues of birds only, but gives more options in backstory for players, as well as providing a way for non elysians to essentially, "gain access" by getting a new body for a time and then switch back afterwards.
It wont necassarily make it more accessible as a faction but will provide more options which seemed like the goal of the neo project whenever i had been in a discussion about it.
I don't mean for this to sound harsh or blunt I had just been watching the thread and thought this seemed like it could be useful to point out for anyone else who may not have known about it.