You say that but, in ARR the first three HM primal where at first optional content that later where changed to a clear condition by time keeper of the lake was added.
Crystal Tower came from the same production time as those.
Printable View
Its nearly identical to the CT in the ARR: A new beginning trailer
https://i.imgur.com/114QIWG.jpg
But they added that 2nd floating crystal shard. I wonder what it could be? Everything else was a flashback to the Calamity, Dragonsong War and all the other cgi trailers, but everything else was kept the same as far as I'm aware. So why did they do that to the CT?
I think the duplicate is just a picture-in-picture effect, not directly foreshadowing anything. You get that kind of arrangement in manga panels sometimes, with a distant shot and a closeup composed into the same panel.
The plot thickens...
But have a look through the rest of the trailer(s) and see if there's anything else that matches that shape, perhaps? It could just be two overlapping shots of different things as it "flickers" through different memories.
Yeah, the clips flash onscreen for a very short time during this portion of the trailer, making it difficult to tell if it's a new shot of the tower or one from the same trailer but from a different angle. I think it's fine to presume that G'raha is the one in the Shadowbringers poster and that he'll play a bigger role in the MSQ next expansion (though I'm still hedging my bets, as it could be an entirely new character under that hood), but using the Crystal Tower's presence in the trailer as evidence is questionable.
It looks like it really is CT, but seen from Coerthas. I guess they decided to combine the two in one shot
https://i.imgur.com/hNRe7AR.jpg
It seems like an odd thing to debate when you can layer those exact screenshots over one another et voila, lol.
Shadowbringers shot (Tinted Red)
Behemoth layer (Tinted Yellow)
ARR CT Top (Tinted Blue)
https://cdn.discordapp.com/attachmen...09/3_Layer.jpg
At this point, yeah, it's a runaway theory that hinges on everything connecting back to (as a friend of mine put it) "being able to identify a Miqo'te by his lips."
But will this be a "the Void Ark is obviously Mhachi because..." runaway theory or a "Zenos is obviously Yda because..." runaway theory? Time will tell!
EDIT
For what it's worth, "let eon become instant" is in some other languages presented as, "let me upend the laws of time and space".