Lightroom 6 has reached the end of its road, so it’s all gravel lane from here on out. The last perpetual revision, Lightroom 6.14, was released on December 19, 2017, and Adobe isn’t going to update or support it going forward. The app still works fine, however, so if you’ve chosen it over Adobe’s subscription offerings (Lightroom CC and Lightroom Classic CC), you shouldn’t see much of a difference for the time being.
Unless you buy a new camera.
If you’re shooting with a camera released after that date, Lightroom 6 won’t recognize those raw files. Camera manufacturers tweak the raw recipe for each camera model, which is why you frequently see updates to Adobe Camera Raw, Photoshop and Lightroom that add new raw formats. Since Adobe ended support for Lightroom 6 at the end of 2017, the software will no longer receive those updates.