I’m still not sure if I can link to the Darko article (but it’s readily searchable). However the bottom line is this.
“The bottom line: it’s only when 1) the streaming app, 2) the iPhone/iPad model on which that app runs and 3) the streaming endpoint are all AirPlay 2-equipped that the stream is lossy compressed to AAC 256kbps.”
Sounds counter-intuitive, doesn’t it? Please note that for lossless he’s referring to 16/44 and maybe 24/48 - nothing higher.
(Also, the article is two years old, so something may have changed.)