I think I did a bad job of describing what I'm after.
I was just going based on the sources you listed, there didn't seem to be any reason to need multiple devices? At most it sounded like you'd just need your personal & work phone connected, and carry whichever one you want with you to consume media from. They sell arm bands and such to hold your phone if you are walking around naked too
The only audio source I can think of that would fall outside of working on a phone would be a record player, but generally you'd have that for the "warmness" of the audio and wouldn't be using BT to listen to it anyways.
Side note: Teams is really good at letting you use a phone and a PC simultaneously. You can join both devices to any call/meeting. Good if you want the audio running through your phone, and use your laptop for displaying the meeting contents.