SP sites modernization and system groups

When modernazing SPO sites the permissions given through AD security groups are not supported. This is clear to me.

But why are the built-in SP systems users/groups "company administrator" and "SharePoint Service Administrator" listed there as security groups? Is this just something to ignore and in modern SP sites there are no corresponding groups? I would like that "Company Administrator" still have access to the site even after modernization so that the IT support and operational staff can access the site and can manage it. Looking for some best practise solution here..