Yes, some of us have stayed at both and compared them but you may be right that there is no dedicated section of the Wiki for comparison posts. Here is my comparison:

https://www.flyertalk.com/forum/31320359-post1677.html

Here is alanslegal's excellent post comparing Conrad Bora Bora, Rangali Island, and Ithaafushi:

https://www.flyertalk.com/forum/31358380-post5.html

I'm sure there have been other comparison posts from poster who have visited both properties, it might be a good idea to gather them all in one place.