there are already some universities in the states and canada that require its users to have anti-virus software installed before they can use the campus wireless network. i'm not sure how they handle mac users.
At all of them, Linux machines were allowed to connect to the network without any fuss, and presumably Macs too. Windows machines were required to install university-provided anti-virus.
There was one little problem where the detection software they were using was checking for SMB support, and I got blocked because my Linux box had something running like that, but I called support and they worked it out.
Every large corporation I've worked for had similar rules and regulations and I left each and every one of them because of it.
Education yes, antivirus no. There are roughly zero active Mac viruses; the real threat is phishing.