Sorta. The old name still works, when referring to a proper old release. Going forward the OS family is referred to as macOS.
I see, thanks!
Officially it's macOS now.
Oh interesting, I didn't realize. Thanks!
Mac OS, then Mac OS X, then OS X, and now macOS. Probably Mac OS again some time soon to go full circle.
I personally just say Mac OS. If there were some device called the Blarg, with an operating system built to run just on the Blarg, then that operating system would be most naturally called Blarg OS; I suspect the vast majority of people would call it that if no name were supplied.
Also, since OS X's full name was always still "Mac OS X", "Mac OS" correctly refers to every iteration of the operating system.
macOS matches watchOS, tvOS, iOS, and iPadOS. Unless Apple decides to rename all their products, I don't see macOS changing.
Yeah, jeez, what's NeXT?
Well then say that MacOS is 3 pixels slimmer than Mac OS but it just doesn't have the same feel and I'm constanly get crumbs stuck between the c and the O.