How do you figure that 'Apple figured it out a few years sooner than Microsoft did'?
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.
Microsoft didn't make the same claims, but they showed the same lax attitude toward security for years. Apple only needed to see a few malware outbreaks to come to terms with reality.
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.