Not sure how to interpret. Pro Qt or pro wx? I'm assuming the latter.
But I don't even agree. Qt is/can lay claim to native as much as anything else on desktop Linux/BSD. The quality of the Windows emulation has always been excellent as far as I'm concerned, at it's been pretty goodish on Mac.
But I've never seen a perfect cross platform library that targets Mac.
wxWindows may use system drawing at the low level, but those that have been in this for years know what's up: it's just an unholy messy quasi-MFC (Microsoft Foundation Class) looking thing - the model is inherently MS Windows from 1994. This is not magically going to work well as a Cocoa app just because it uses NSViews under the hood. And although the simple controls may use the OS, all the complex ones have tons of internal design. Like this is optimizing the wrong thing - as a normal person I probably care more about the look and feel of the tree view, whereas only the weirdos on here are going to get bent out of shape that some button text is a few pixels off - getting both right is nice, but only hitting the last one is pointless.
I've never seen a nontrivial wxWindows app that would fool anyone on MacOS. Qt can get much closer if you work at it a bit. So in practice I would say you can do better with Qt for the major desktop targets.
These are all compromises. And native hardly means anything these days. Yes Windows has what has been retconned as WinForms, but otherwise, the UI LnF of Mac OS is a constantly moving target and Windows has never been as consistent as people seem to believe. Linux/Desktop Unix - lol.