FLAC was released in 2001 and widely popular by at least 2006.
With much fanfare, iOS11 (2017) was the first time iOS supported playing FLAC files and that was (and still is) not the Apple-branded “Music” app but only in the “Files” app.
Vorbis has been pretty much entirely obsoleted by Opus so there wouldn't have been much incentive for new Vorbis support since then - is there a similarly decisive open successor for FLAC?
I certainly have not seen one. FLAC is either A) the best option for free lossless music encoding, or B) The music industry is way too big of a heavy hitter to let any others build momentum
