After seeing tons of wow movies, most of the UIs are filled with unnecessary shown frames...
So why not make an addon that makes an alternative alt+z keybinding or a slash command, that hides every single child frame to UIParent, but the ones you have written in a table, so that you can hide all the frames that you really don't need to watch in a wow movie - an example could be the minimap.
And also make it possible to clear the frames point and set a new one during this mode, and make it return to normal as you swap back. So you really can make a filming UI just by clicking on a button and swap back to your normal UI as you click it again.
My idea to make this possible is to make a new frame: could be UIParent2 with WorldFrame as parent and make all the frames in the table reanchor to UIParent2 when you click this keybinding/write this slash command and then hide UIParent as the normal alt+z does.