> I think the chance for remote execution would be far less if they used unix based systems.

OSX is a *nix based system and has had far worse security than Windows for ages (lagging with basic things like address space randomization). Just because Unix is not considered a primary attack surface area for viruses and alike, it does not make it inherently more secure. That kind of attitude is indeed even more dangerous than having a well secured Windows computer.

(Disclaimer, Mac user myself)