If a course is set up for separate groups, when a user doesn't have a group and access the participants it is empty and there is an informative message:

• On LMS (browser) - the message displayed is 'Sorry, but you need to be part of a group to see this page'
  
• On the Moodle App - the message displayed is 'No participants found for this course'
  

I think the meaning is completely different even if the behaviour is the same (no participants are displayed)