Making a big interpretation that could be possible =/= having sufficient backing to give a possibly rating. There are many points that were brought up against that.
Never said it exists in pieces. But the portion of the garganta that is technically functioning as boundaries between the worlds that separates them, can be destroyed partially. The destruction doesn't have to be whole.
Firstly there are not many points, I ask you to write them because nothing has been brought up except damage Dangai explanation.
And I already explained it,
you have to look at that scan after reading the final chapters for the context of what Yhwach was doing, Yhwach was starting to destroy everything from soul society.
The destruction clearly started on Soul Society, so if you really want to argue chain destruction (which is not implied by Yhwach) it would be:
Soul Society Dimension cease to exits by Yhwach's hand > Dangai fall > Living World fall > Hueco Mundo/other dimensions > everything is mixed even concepts > Primordial world.
Yhwach even opened a portal to went to Soul Society from another dimension, if his plan was to destroy Dangai he should have opened a portal inside it. But he didn't, because he never mentioned once it was his aim.
Yhwach was clearly conscious of his capabilities of destroying everything and bring back the primordial world from Soul Society.
And for the tiering read, last Cyber long post.
And yes
they are the same thing given the context.
And this chain reaction stuff is too much abused. Yhwach feat had been proven to being different from Dangai destruction regarding Quincy.
So there is no chain reaction, It is never implied once. Neither by Yhwach, neither by anyone.
Why we cant take at face value Yhwach's claim? they are not contradicted by NOTHING.