Did you try again today? There is a new patch since a few days ago - web_20200630_00_rc00 - it is working now for me and other people. Read here -
https://community.wd.com/t/wdtv-live-doesnt-play-youtube/253059/18 ,
and https://community.wd.com/t/youtube-freezes-black-screen-in-wd-tv-live/253162/6