.. no one uses Linux as a desktop..
More people use Firefox and Chrome than IE across a whole lot of OSes and versions of Windows, though the latter browser is much more targeted despite the comparatively lower number of divulged vulns.
there have been several self replicating viruses / worms that didn't even need user interaction on Linux.
Too much smoking is no good, even for an AC. Or, you're talking about those proof-of-concept ones that are created and live in labs only?
you are far more likely to be hacked if you run Linux than if you run Windows
Any stats to support that? Whatever you install, it always up to you to insure an easy hack:
1) weak credentials, password, easy to guess username, allowing root for ssh, password logins, writing your login credentials on your (friend's) forehead, using a Windows machine to keep it/login to it etc
2) failing to update your system for security fixes
3) misusing apps on web/mail servers, like bad php-coding, WordPress plugins, turning extraneous Apache plugins etc
4) using crappy (in-house) sql back-ends or/and writing bad sql code to allow an easy sq-injection
5) with 4 stupidly ignoring the rule # zero to never store your users credentials in clear text or without proper hashing and salts.
Those and more apply to both Windows, Linux, FreeBSD and even OpenBSD, however, you still don't see any other web/mail servers to utilize AV, other than when they need to filter it for Windows client machines.