Useless comment, but let's go with it anyway
You are correct, the Apple 3.5" Dongle DACdoesn't pass through digital audio, it is a DAC in itself that outputs analog audio output. There is no way there was a valid comparison between FLAC and Apple Lossless with his set up.
Can I listen to lossless audio using the AirPods Max Lightning to 3.5mm Audio Cable?
The Lightning to 3.5 mm Audio Cable was designed to allow AirPods Max to
connect to analog sources for listening to movies and music. AirPods Max can be connected to devices playing Lossless and Hi-Res Lossless recordings with exceptional audio quality.
However, given the analog-to-digital conversion in the cable, the playback will not be completely lossless.
Another useless comment, and much worse as it misquoted me, here is my post around that quote again:
So, I haven't done the comparison myself, but I trust "Miguel's" comparison for now.
For my use this isn't an MQA comparison, it is a Sound Quality comparison, the non-MQA recordings often sound better on Tidal than AMHD- and there are far more non-MQA recordings on Tidal - with no MQA version available.
Comparing Tidal - Masters and non-Masters - Tidal often sounds better than Amazon Music HD, but there are times it is the other way around too. Usually due to each service having different recordings available for that track or album from that artist.
Both Tidal and AMHD have complimentary music catalogs too, I find both have recordings the other doesn't often enough to keep both services, rather than only have one service.
If you want to enjoy Apple Music Lossless, then you need to find another option to output Apple Lossless music than the Apple 3.5" Dongle DAC.