I develop Mac software and support my software via email. The problem I always had with "OS X" is that users who don't know what an "OS" is, didn't seem to pars

I develop Mac software and support my software via email. The problem I always had with "OS X" is that users who don't know what an "OS" is, didn't seem to parse "OS X" at all (they would reply back as though it didn't appear in the sentence). They certainly didn't associate it with their Mac – apparently thinking it was just some weird sigil that the geek in the internet computer machine had included for no reason. I always had to say "Mac OS X Lion" (or whatever the big cat name of the year was) to get any level of understanding. "macOS", for all its initial lowercase goofiness is at least understood by most users.