I assume you already tried disabling WiFi power saving in the steam deck developer settings, right? Just asking because you mentioned this in neither of your two posts and because I also fixed my 5GHz connectivity issues this way.
EDIT: Nvm, overlooked it in your first post.
How is PulseAudio still there? I mean, sure the protocol is still there, but it’s handled by
pipewire-pulse
on most systems nowadays(KDE specifically requires PipeWire).Also, PulseAudio was never designed to replace ALSA, it’s sitting on top of ALSA to abstract some complexity from the programs, that would arise if they were to use ALSA directly.