Shouldn't casting FLAC on Chrome to a Chromecast be a priority? I may be a curmudgeon, but I have way too many CDs in storage in those 80 litre Rubbermaid bins that I only ever see as FLAC files on the media server.
The Chromecast can receive and play FLAC since 2015 (I can't find the exact dates on any release notes but [1][2]).
This is about adding audio/flac decoding into Chrome; meanwhile the Chrome -> Chromecast communication is entirely proprietary (notwithstanding the APIs), so Google controls both ends. Since so much of the Chromecast is about handing off content [3], there's little need to implement FLAC encoding in Chrome because the Chromecast can just be told to load the native (original) stream itself.
