I don't give a hoot about operating systems. But, I fail to see how drawing a conclusion with no information can be reasonable. In fact, it would seem to be arbitrary - the opposite of reasonable.
Well, let's see... there are over 1,000,000 known malware out in the wild for a specific publisher's OS which is used ubiquitously in many such buysiness applications... and only 17 for a competitor's operating system which is not used ubiquitously in such applications. Is it therefore unreasonable to make a conclusion as to WHICH operating system just MIGHT be running that wound up infected with a Trojan? Especially since the 17 that run on the competition will not crash or affect other running applications on that OS. I really don't think so. I think the preponderance of the evidence makes the conclusion reasonable... and obvious.