The solution is simple but it's a wonder why VBOX doesn't address it directly?

Perhaps newer versions will but you have to add your user to the "vboxusers" group and then login and logout and you'll see the devices you wanted but couldn't access are now available.

The weird thing is that the grayed out issue doesn't happen with all devcies but one notable thing is the Apple iPhone especially in DFU or Recovery Mode which is an big issue for some people.