Use SharePoint Active Directory Import - User Profiles
Instead of using the default setting of synchronization of User Profiles, you can select the "Use SharePoint Active Directory Import" setting. Which is a lighter version and which only imports information from the AD. If you had a connection before, it is lost when you click on this setting.
First you need to create a new connection again. You will notice a good difference here: you can click on "Filter out disabled users"! Very good.
You can no longer click on "Edit connection filters".
You cannot edit the User Properties, such as adding the thumbnailPhoto to the Picture property.