Disable assistants on my Android headphones

So I wanted to use the button on my Android headset to control the audio of the application I was currently using: a book reader or a music player or something similar like that. And instead an annoying assistant was blinging annoyingly and impotently in my headphones, while my music was still on. It is not at all obvious what does that and how to stop it. And there are two assistants on my phone: Google Assistant and Bixby. Turns out you only need to care about one.

Here is what I tried and didn't work:

• disable assistants
  • Bixby can't even be disabled
  • Google Assistant can be disabled, but by that it means it doesn't listen to your voice commands anymore, buttons are fair game
• apps to change the action for the headset button
  • they either don't work right or can't work when the screen is locked
  • the "many apps" recommended by some articles are not even in the store anymore
  • they need full control permissions on your phone

So, here is what you need to do:

1. have your headphones connected to your phone
2. open Google application
   
3. tap the three dot More button
   
4. go to Settings
   
5. select Google Assistant
   
6. go to Devices (it's a section in blue on my phone)
   
7. you should see Wired headphones (or maybe something else depending on your headset type) - tap it
   
8. uncheck the option Get help from Google
   
   
   

That's it! You don't have to disable the assistant on your headphones, but your headphones in your assistant. And this is regardless of whether the assistant is "off" or "on". Now you can listen to your music and books in peace.

"But, what about Bixby?" you will ask. As far as I can see, Bixby is something that comes over Google Assistant. I did disable some stuff in it, but I doubt it was a problem to begin with.