What you are seeing is called storyline progression, and no the Corsairs are not being deleted from Omicron space. That is simply too absurd to even comprehend.
It's been a rather long day so I'll be quite blunt, this entire thread is nothing more than rumour and wild speculation. The Story team frequently consult factions both official and unofficial regarding changes, we also discuss matters with those knowledgeable in certain regions or factions if no one else is available. We can't always carry out the suggestions given to us but we do try to strike an even balance.
Beyond that you can think whatever the hell you like, it doesn't make it true.