Explanation
A Salesforce Console application is designed to optimize the user experience for service representatives who work on multiple records and tasks at the same time. The console navigation features allow the user to access multiple records and related information in a single screen, without switching back and forth between tabs or windows. The features that are relevant to the designer recommendation are:
More than one detail item can be open at a time. This allows the user to work on multiple records simultaneously and switch between them easily.
Multiple subtabs can be beneath a single parent record. This allows the user to view and access related information, such as activities, emails, notes, and attachments, without leaving the parent record.
A split list of records and individual record detail can be seen on the same screen. This allows the user to browse through a list of records, such as a queue or a report, and see the details of the selected record on the same screen.
The feature that is not relevant to the designer recommendation is:
Service representatives with lower resolution monitors will have a better user experience. This is not true, because a Salesforce Console application requires a minimum screen resolution of 1024 x 768 pixels to display properly. Users with lower resolution monitors may experience scrolling issues or truncated information.
References: What Features Are Available in Lightning Console Apps?, Personalize the Navigation Menu for Lightning Console Apps, Navigate Around