Yotsuyu's line is actually very familiar to me. I remember an aphorism that was something like "trees are ripped up in hurricanes, but reeds bend," which is close enough to what she's saying. It's supposed to mean something along the lines of "accept change or you will be left in the past," which to her credit does seem to be what Yotsuyu is telling people. Only by embracing change can you find hope and freedom; clinging to the past results only in misery (see: Dragonsong War). The problem is that the kind of change Garlemald brings... isn't wholly good. (Other than technological advancement it's wholly bad, actually.) Being someone who has benefited from the change Garlemald brought to Doma, Yotsuyu would naturally try and push others to do so as well... or use it as an excuse to abuse her power and tyrannize the citizens.

Midgardsormr's comment on our strength... well, to be philosophical about it, he probably wasn't talking about our combat prowess, but our resilience and fortitude. Hydaelyn allowed him to seal away the Blessing for the express purpose of showing him why we are Her chosen, and the sheer amount of crap we went through from 2.55 to 3.0 (End) without losing our way did just that. Note that strength does not equate to power - while we might have more resilience and fortitude than anyone else, that doesn't mean we're the greatest fighter on Hydaelyn. From what we've seen so far Zenos appears to be superior to us, at least in terms of raw power, and we'll need to find a way to bridge that gap one way or another.