I'm aware that they are product names, but also very much "versions" in the public mind too. I guess that falls into the difference between build version and major version. People choose a major version for features, and get a build based on that version with the latest fixes but don't generally care what build. Even Dolphin is showing this split with their yymm-patch format for builds between releases.

Ironically, I was going to cite the humorous example of Sun and Solaris - the successor to SunOS 4.5 was identifiable from the OS itself (e.g. uname) as SunOS 4.6, but branded as Solaris 2.6 and older versions of SunOS 4.x were retro-actively labelled as other Solaris versions. They followed that by renaming Solaris 2.6 to Solaris 6 when they released Solaris 7, and again uname used the older format and returned SunOS 4.7.