To turn off SharePlay on your Apple TV, follow these steps:

  1. Open the Settings menu on your Apple TV.
  2. Go to 'Users and Accounts'.
  3. Select your username.
  4. Choose 'Shared with You' or 'Share with you'.
  5. Turn the setting off by toggling the switch.

To disable SharePlay on an iPhone or iPad, if you never (or almost never) want to use it:

  1. Open the Settings app.
  2. Tap on 'FaceTime'.
  3. Select 'SharePlay'.
  4. Toggle the switch to turn SharePlay off.

Keep in mind that SharePlay is initiated by a FaceTime call on an iPhone, iPad, or Mac, and if none of the Apple TV users are in a FaceTime call, SharePlay shouldn't interrupt your shows. To ignore a SharePlay invitation initiated by someone else, turn off 'Shared with You' or 'Share with you' on your Apple TV.