We run a lot of PCs in my business (necessary for business to business connectivity to use MS software) and also several Macs. There used, years ago to be significant differences between PC and Mac but certainly since OSX and the arrival of things like unix and office 365 the differences have largely disappeared. In these days of constant phishing, malware, spam and regular hack attacks, high security, whatever the platform is essential. Firewalls, encryption, sophisticated cybersecurity tools (expensive!), key logger detection, dual authentication methods, staff awareness and training are all necessary and routine tools in the armoury now. Personally I take the view that sticking with old operating systems reduces not enhances security and on-line safety. Windows 7 is already pretty old now - sticking with it just makes the eventual need to "upgrade" (term used with tongue somewhat in cheek) a more challenging and bigger step. I feel much the same about Apple - the upgrades are necessary to stay safe but they benefit Apple (global mobile platform operator, manufacturer and virtual bank that it is) more than the typical consumer.
It is a sad fact of life that we need all this security. I doubt that there are many people now who don't know someone who has suffered fraud or ID theft.
Personally I would not let someone walk off with my backups. Especially the device holding my only one. We can all learn lessons from this illuminating thread.