That all makes sense to me, and it's less convoluted than the old EU's idea that while pockets of Sith-controlled regions sprang up across the galaxy, the Republic never truly "fell," and all the "thousand years" references in the PT referred to a reformation of the Republic after the destruction of the old Sith.I think the "hundred years darkness" by way of Sith rule was referenced briefly in the Tarkin novel and there's some stuff in TCW that makes oblique references to that period like the lightsabre master builder droid who's been on that Jedi ship (which spots the Old Republic seal from the SWTOR MMO no less) for *over* a thousand years and the Mandalorian Deathwatch bloke who's name I forget (Vizlar?) bragging about how the darksabre was looted from the Jedi Temple "during the fall of the Old Republic". Sidious also mentions how the old Sith Empire was built on the backs of slaves in the two or three parter that dealt with the race of slavers."It's only relatively recently that they've officially slid back to the idea of the order being older than that, though I don't think they've ever explicitly brought up the 25,000 year timeline thing again."
Where have they mentioned this in a newcanon story? Im actually curious...
It's mostly oblique references so far, but it looks like the official canon is that there was an "Old Republic" and it fell, followed by a century of Sith rule. From what's said in the PT about the Sith having thought to have been "extinct for a millennium", the Republic not having fought a war or had a standing army in a thousand years and so forth we can safely intimate that the Jedi eventually defeated the Sith and helped restore the Republic.
There were also lines of dialogue in Episode III that can support your inference. After going full-Sidious, Palpatine said something like "Once more, the Sith will rule the galaxy!" and during their duel Mace Windu said "The tyranny of the Sith will never return!" So clearly the galaxy (or a significant portion of it, anyway) was under Sith domination for a time.
I do remember some of the clone troopers in TCW referring to "the Old Republic," too.