As first reported by AFTVNews, it appears that Amazon is deprecating the native Luna apps for Mac and Windows. The apps have been removed from documentation pages. Also, from the site that lists how to play Luna on various types of devices.
While this definitely isn’t positive news, desktop and laptop users (including those on ChromeOS in addition to Windows and Mac) can still play Luna via the browser at luna.amazon.com. The web-app can also be installed as a PWA. So, presumably Amazon is trying to eliminate the extra effort in maintaining these native apps.
We are more concerned about the continued leaking of games from the service – with more games continuing to leave than join. Specially, including the fact that some of the best games still left on the service are leaving in June.