Strange behavior with 'Browse Users' permission

A user with 'Browse Users' permission has the ability to search for users in user picker fields in the 'Issue Navigator' (e.g. Assignee, Reporter, etc) just by typing the user full name (e.g. Bruno Rosa, Clarissa Gauterio, etc). The user can't search by usernames though.

If the same user doesn't have 'Browse Users' permission, they are not able to search by full names in the 'Issue Navigator', which is an expected behavior since the user doesn't have the appropriate permission, however, they are able to select all the users in the instance by typing their 'usernames' instead of their full names.

Is this an intended behavior?