Apple tried to claim Apple PCs were special, but it didn't remove the single biggest hazard to any claim of security. PC means personal computer, which means a system owned by millions of people without the technical skill to assess whether or not that attachment (whether it's birthday_card.dmg or birthday_card.exe) really came from grandma. All PCs are vulnerable to users. I'm glad Apple figured it out a few years s…
I don't endorse Windows. But for all Windows' brokenness, Microsoft has not claimed invulnerability to viruses and has put a significant amount of effort into improving security from XP to today. The main reason it has had more trouble with malware is that it has been a much more popular platform, meaning that is where all the victims are.