Virii are not the only malware ...
... that concern me. They tend to be destructive, overt, and [relatively] easily discernible. I'd be much more concerned about key-loggers and the like.
Even with my limited experience, I've already seen software that proclaimed the ability to be installed - or self-install - w/o admin authority. 'Twould be no great feat to make such an installation transparent to the current user. In truth, how do you know you're not infected right now? As in any security issue, you never know how good it was until it fails - then it wasn't good enough.
Apple went decades with the brag that they were virus-proof - one (1) of their brags of superiority over Windows. But I've seen a number of malware incidents mentioned in the last couple of years, after their user base increased. Since, in fact, they switched to OSX - a *nix derivative.
Sorry, Jack, but I don't find your conclusions tenable. Not all malicious intent is readily discernible. And the successful thief is the one who gets away. You'll only know if you've been attacked when something overt happens, and then it's too late. I can appreciate the thread of your thoughts, but I consider it foolhardy, at best: there's an old saying, which I can no longer quote, to the effect that whatever Man can build, Man can destroy. This falls into that venue.
