You will most likely find you have to support both at this time if you want to reach as many users as possible, especially if the content is encrypted.
iOS and Safari typically use HLS and FairPlay, Android, Firefox and Chrome use DASH and Widevine and Windows and Edge use DASH and PlayReady.
At this time, Apple iOS devices must use HLS for content greater than 10 mins over a mobile network:
2.5.7 Video streaming content over a cellular network longer than 10 minutes must use HTTP Live Streaming and include a baseline 192 kbps HTTP Live stream.
(https://developer.apple.com/app-store/review/guidelines/)
For this reason streams served to Apple devices are usually HLS, while DASH is used for other devices.
If you streams are not encrypted you can use CMAF a single source file. If they are encrypted then it will be some time before devices support a single CMAF encrypted source - See more detail here: https://stackoverflow.com/a/62020034/334402
CMFA info here: https://developer.apple.com/documentation/http_live_streaming/about_the_common_media_application_format_with_http_live_streaming