Moving Site: Is Re-downloading Files After Changing URLs necessary?

On the Wordpress Codex: Moving Site page under Changing Your Domain Name and URLs, it states that you should re-download your site files (Step 5) after changing your site URLs (Step 4). Is Step 5 actually necessary? Wouldn't changing the site URLs only impact the database?

1. 
   

   Download your existing site files.

   
   


2. 
   

   Export your database - go in to mySQL and export the database.

   
   


3. 
   

   Move the backed up files and database into a new folder - somewhere safe - this is your site backup.

   
   


4. 
   

   Log in to the site you want to move and go to Settings > General, then change the URLs. (ie from http://example.com/ to http://example.net) - save the settings and expect to see a 404 page.

   
   


5. 
   

   Download your site files again.

   
   


6. 
   

   Export the database again.

   
   


7. 
   

   Edit wp-config.php with the new server's mySQL database name, user and password.

   
   


8. 
   

   Upload the files.

   
   


9. 
   

   Import the database on the new server.

   
   

If it is necessary to re-download the site files, would it only be the root folder and /wp-content folder that might have changes? Aren't those the only areas where changes are made to Wordpress' core files?