Bose sound bars meet all your requirements. They have microphones but the mute button on it is a hardware disconnect of the microphone power. You can play audio over Bluetooth. Also has hdmi arc. You won’t be able to use Home Assistant though.
Nice, and I actually did find one that doesn’t seem to have a microphone at all (www.bose.com/p/…/TVSPKR-SOUNDBAR.html). I thought I had looked at these before and discarded them for some reason, but maybe I just looked at the wrong models.
Regarding Home Assistant, I think I can pull it off with a RPi connected with AUX to the speaker. So that was one of the things I was hoping someone had some experience with here, either balenaSound or Snapcast or something similar.