The Nexus 5X and 6P were released in October 2015, and ended up being the last devices under the Nexus brand. The following year, Google released the original Pixel, marking an end to the company's lineup of affordable devices. Google has now confirmed to Ars Technica that Android P will drop support for the 5X and 6P, along with the infamous Pixel C tablet.
The 5X and 6P still have a large development scene, so there's no doubt custom ROMs will continue delivering major updates to both phones. The Pixel C has a much smaller developer following, but LineageOS does have official builds for it.
Android P might also mark the end of support for the Nexus Player, Google's first and only consumer Android TV device. It was released in November 2014 with Android 5.0 Lollipop, making it the longest-supported Android device from Google on record. There are no Developer Preview images for the Nexus Player, seemingly indicating that Google has finally dropped support for it, but we are still waiting on confirmation of that.
The Nexus 5X and 6P will continue to receive security updates from Google until November 2018.
Google has confirmed to us that the Nexus Player will not be receiving Android P.
- Ars Technica