One thing that seems to be overlooked. Macs OSX machines are more expensive, ergo they are used by more upscale people with a probability of higher incomes. Now if I were targeting people to pilfer bank accounts etc. Who would I target? Yes Macs have a smaller market share, but that does not necessarily make them safer. A study should be made of how many Macs are attacked in total as compared to the number of Macs out there. That will give you the risk factor. If say 2 out of 15 macs get attacked but 10 out of 85 PC’s get attacked, the percentages are almost the same.
Nice theory... if it was only true that it happened relatively more often... LOL...
The major threat out there today are criminals looking for money. There is no profit is destroying your hard drive but there is a huge profit potential to compromising your server or machine.
The next motive is theft of information. Information that can be used to make money or for national interests.
The weakest point on any system is the user. If you can get a user to take a certain action you can do just about anything.
If you have to spend a lot of money or time developing an attack would you target 5% of the target population or the 95%?
Your point about income differentials is a good one. However, the ‘market share’ canard has been completely debunked. Do a search on the “witty worm”. It’s a worm from a few years ago that was written and exploited even though the target universe was some 15-20k systems total. I suspect there are a few more than 20k Macs out there. If there were an easy way to subvert them, it would be done.