We occasionally field questions from customers' admins around how to suppress some or all users from the /about page.
Hiding with CSS is possible, but incomplete.
I suggest adding a setting suppress_fom_about_groups that would easily let site admins perform this operation.
To hide all admins/mods, they could add e.g. staff or admins to this setting, but to be more selective they could use a custom group.
Discuss this on our forum.