A sense of... despair, is what comes over her.
She tried to explain, and it just bounced off.
They're still trying to reassure her that she's free to, and encouraged to, optimize within the setting.
Even if the GM winds up banning manufactured diamonds, which they seem to be on the fence about. (Do they not realize what she could do with diamonds?)
They don't get the scale of the problem.
They still think that their setting is workable at its core, and only needs a few problem spells removed and a handful of customized justifications for why no one has tried one thing or another yet.
They don't get that "Europe circa 1750, mostly farmers, except, just stapled on, some people can violate the conservation of mass and energy on a whim," is, for all its representation in fiction, not a normal place.
They have no conception of the fractal impossibility.
The GM has this vision where intelligent and creative people use the spells that exist in the Pathfinder Roleplaying Game against the monsters that exist in the Pathfinder Roleplaying Game, and the GM thinks they'll get a long and interesting story out of that, and they can handle whatever problems come up with lampshades and spot-removal and tweaks.