Apple (IOS, Apple TV 4K etc) only support HLS so the BBC are probably going to have to provide HLS streams for quite some time (even if they have deprecated HLS in favor of DASH and don't provide 1080p and 4K in HLS).
A contender to replace HLS/DASH is Common Media Application Format (CMAF) which uses the fragmented mp4 (fMP4) technique used by DASH rather than Transport Stream (TS) used by HLS. It should be noted that the HLS specification also defines support for fragmented mp4.
A common DRM may be implemented using CBCS (used by Apple Fairplay) replacing the CTR scheme used by Widevine/Playready.
Apple, Android, Xbox, Firefox, Chrome & Edge already support CMAF so maybe a common video streaming format is beginning to emerge.
EDIT: Removed erroneous conclusion and corrected some of the above description of CMAF.