In open beta you can disable the mutual friends section, Its job is to hide your mutual friends with others.
If another user has the setting enabled, they can see anyone who has the setting enabled, The info prompt for the setting indicates No friends should be visable after disabling this setting.
This setting currently works Per user, Not global as it discribes itself.
Image examples attached.
ComfyChloe has them disabled, an alternative account has it enabled, I can see the mutuals of comfychloe while its disabled for them but enabled for the viewer. (It disappears if the viewer has also disabled it)