We (well @Darmur) had similar issues with the pi0 - the Audio jack doesn’t show up.
Are you running on a pi4? I really hope these bootflags do not need to be tuned on a per-pi basis!
What was the final combination that worked for you? Could you share the output of aplay -l?
Found some hints:
So snd-bcm2835.enable_compat_alsa=1 snd_bcm2835.enable_hdmi=1 should work as before?
EDIT:Looks like they disabled the audio jack for the pi0