That's not really true. I mean its not entirely, its partially true. The main reason is because a Windows platform is not only more susceptible but much more widely used.

I've worked heavily with UNIX for a while and have seen it's fair share of quirks. Most phones today employ a mixture of UNIX/Linux within themselves and most of them are easily hacked to allow the user Super User access.

I must say, I wish Windows was more of just a GUI front end on a UNIX based system. It seems so much more stable and I think that's where Mac really has Windows beat, the stability, not necessarily the security.