I think it wasn't flavor text where you read it. The only talbot text mentioning linen is Scarab Feast, which is from Amonkhet, but not describing at all what you said...

Oh I'm not saying it's the only reason Amonkhet might have bounced back pretty soon, I just didn't spot it in your previous post. Amonkhet was, by design, a place to rapidly replenish the population. Therefor I believe they'd be uniquely equipped to recover from great losses better than, say, Innistrad would. Ever since HoD there's been no more reason to waste lives in the trials, especially with most of the Gods gone. Old people might have a chance now.

I'm also not sure if the timeline is the same as the real time difference between HoD and MoM as a set, there might have passed a little more time in-plane than just the 6 years difference that we had?

Amonkhet was a breeding pool for warriors when we visited first. What you might miss is the reproduction rate for its citizens. The whole plane was designed to pump out babies barely growing up before they had to prove themselves in the trials before dying young. The Hour of Devastation probably led to a baby boom among the survivors, and minotaurs, jackal- and snakefolk might be able to replenish the legions inbetween wars at a higher rate than you think just humans would. Without the actual trials in place anymore, which sounded as deadly as most wars to me, it would be that plane to bounce back the quickest from massive losses caused by interplanar conflict.

No, it won't. Warped Devotion mentions a permanent, and in Magic an object is only a permanent if it's on the battlefield. It would have to mention "permanent cards" if it would include Parallax Nexus in the options.

So only Cyclonic Rift- or Unsummon-like effects will cause a player to discard.