"Any Apple OS is just as vulnerable as any Android or Windows system out there..."
Yuhuh, you keep telling yourself that. Even if it were true (which it isn't), as soon as Apple release a patch any iPhone back to the 5 1/2 year old iPhone 4S can be protected on the day of release (depending on user apathy); for free. Android has nothing like this. OSX El Capitan runs on Macbooks from 2008 onward; my kids have two of these. Fully patched and supported.