Apple doesn't even have a maximize button. I believe you're referring to the green(+) button which is technically called the zoom button. I refer to it as the optimize button since it resizes the window based on the content and when appropriate, will maximize the window to fill the screen. There are a few instances where the button does something completely off the wall, like in iTunes where it shrinks it down to the mini-player. If Apple is guilty of anything, it's not having a consistent function for that button. It's a wildcard.

I'd say the maximize button is in itself a bad design idea. Hit the green button on the browser window and it will expand to the width (or height) whereby scroll bars are no longer necessary. This 'maximizes' your screen real estate, rather than blowing it all on one window/app like a Windows maximize button. Also, while it's not a bad idea to keep page widths in the 750-1050ish range, No True Mac User would object to using their UI controls to optimize their viewing. I mean that's why they're there.

I don't see how the constraints of one system, whether they are right or wrong, really affects the ability of a UX designer to recognize and work within those constraints.

Although I highly agree with you on how Apple messed up by making "maximizing" such a pain, at the same time, I (not a Mac user, but had to use one for work for around 5 months) almost never have my browser maximized, even when on multiple screens. So it's still a valid point that Lewisham brought up.

This website gives the impression that she still needs some practice in her UX design skills.

Get the app "Cinch" from the app store if you're on OSX, and especially if you're on a big monitor. It's frankly better than a maximize button, as it also lets you do side-by-side half screen windows.

(I am not associated with this app, just a happy customer.)