Google has made a change to the resolution options in the YouTube mobile app for HDR videos. The resolution now maxes out at 1080p, regardless of the display of your phone. Resolution options on the Galaxy Note8 Previously, the resolution options went all the way up to 4K, provided you had a Sony Xperia XZ Premium. For most other flagship it was going up to 1440p. The limit is likely being put because of how bad HDR video performance is in the YouTube app. Even on flagship devices, including Google's own Pixel 2, playing HDR videos over 720p caused massive frame drops and a...
Source: https://www.gsmarena.com/hdr_videos_in_youtube_mobile_app_now_capped_at_1080p-news-28097.php
