The GNOME 3 desktop environment was officially released in 2011, and in 2020 we are still on version 3.x. Yeah, despite many massive changes over the last (almost) decade, we have been stuck with point releases for GNOME 3. For instance, just yesterday, GNOME 3.38 was released. Historically, the stable releases all ended in even numbers, with pre-release versions ending odd. For fans of the DE, such as yours truly, we have simply learned to live with this odd versioning scheme.