Netflix has updated its support pages with new mobile devices it is supporting for both HDR and HD playback. Among the list of devices added with HDR support are Samsung's Galaxy Fold models (4G/5G) as well as Samsung's new Galaxy S20 range and the Galaxy Z Flip.
https://www.notebookcheck.net/Galaxy-Fold-Galaxy-S20-range-among-those-added-to-Netflix-HDR-support-list.456083.0.html