USS Einstein wrote:
Why? The Expanse was gone before the Federation even came into being, so why does it matter?
For the reasons mentioned above - like the removal of the Expanse would have been the most important event in history - yet nobody has even mentioned it.
Nobody mentioned it because it was never relevant to anything that happened in the other shows. (And also because ENT hadn't been produced yet, obviously.) The Delphic Expanse was 50 light years from Earth and extended over 2000 light years, regardless of how little sense it might make.
By the way, Trek BBS has a multiquote function that allows you to respond to multiple quotes without having to post four times in a row (which is kind of frowned upon).