There's a YouTube series "Chronicles of a Realm" (search YouTube for "[FFXIV 1.0] Treasures of the Main |1.0 Limsa MSQ | Part 1 | CoaR" and you can find the four episodes or so they did) that shows 1.0's storyline. You can watch one episode and every time he says "The air VIBRATES" and "The air VIBRATES once again", that's the transition into and out of the Echo flashbacks. As someone that started in 2.2 and wasn't a 1.X player, I could see how that would have been super confusing for people playing the game the first time. You can even interact with characters in the flashbacks, and the Echo would somehow insert you into their memories so they would remember you if they met you later in some cases.

Needless to say, give it a watch and you'll see why they might have changed it.

Though it would be interesting to give a nod to the original form sometime and make some kind of statement about how the Cataclysm somehow changed it...but some retcons are just left hanging like that, and I get it, there's no way to tie up ALL those loose ends in a way that makes sense.