Precedence rules for config?

Yes they are

If you want to see the precedence exactly then take a look at

From more specific to less specific

  • flag values
  • remote specific environment vars
  • backend specific environment vars
  • config file
  • default values

I note that rclone may be frustrating for NixOS because it writes tokens back to the config file.

There has been some discussion on GitHub about writing to a separate file and leaving the config file as read only.