And a bunch of those are using Wine, which requires mapping code at the zero page, so they're compiled with a special load command that allows them to map the zero page.

On Yosemite, 64-bit binaries aren't allowed to do this.

Whoa, seriously? I didn't realize Wine for OS X was real enough to be usable for anything, let alone be admitted to the app store and make it to the top. That's pretty awesome.

Although every time I go "I didn't realize X on Y worked", it seems like games are the rationale, and not very surprisingly, since they exercise a relatively small part of the API surface apart from OpenGL. (Mono, some HTML 5 things as mobile apps, and Humble Bundle's asm.js collection all come to mind.)

Can OS X take a cue from iOS and require a special Apple-signed entitlement to do this (unless root overrides it in a config file), or is it not worth the trouble?

Also, does Wine actually require this in general? My understanding was that Wine needed this for legacy Windows apps that themselves map the zero page, but recent-ish apps designed for XP or later shouldn't do that, right?

Wine on OS X has been stable enough for gaming for years! Sims 3 used it, as does EVE Online, and quite a few other major titles, mostly those from EA. They all use TransGaming's Cider fork though, I'm not sure if TransGaming every contribute back to the Wine community these days.

CodeWeaver's Crossover is quite good as well. It can play Skyrim on my 2012 MPB with decent quality. I mostly use it for older games though - rollercoaster tycoon and the like.