WINE is a completely different story. It's (very) far from being a reliable solution for end users, Linux itself does a decent pre-filtering of tech-savvy people, it does not try to integrate with packaging and, last but not least, it is not advertised as a feature for major Linux distros. OS/2 is one example that showed that you *can* get too good in emulating windows. Very few people bothered to write OS/2 specific apps as users could run the DOS or windows version anyway. And then when windows introduced APIs OS/2 couldn't match around Win95, it was game over, as there was no serious native app-base to fall back to.