Ohhh no... As a person who regularly builds random shit for film and television, the single slotted screw is the bane of my bloody existence. Some designers fucking love em for the aesthetic but the cam outs on them are terrible. Is it technically easier to produce? Yes, is it viable to use for construction purposes comparitively - fuck no. Every time you cam out ( lose traction on the screw) you risk accidentally damaging whatever medium you are screwing into.
Locally there is an insane institutional preference for the Robertson screw (which is basically a square) because it doesn't cam out much, drives in well and arguably resists stripping better than a Phillips... This is believed in so much that any screw not seen by the camera is a Robby (usually size 2) while anything that is perceived by the audience is a phillips or a single slot screw. Given a choice nobody wants to handle single slots and chances are good you only find them in period specific builds or when the designer is a psychopath.
As a Set Dresser/On set dresser - any set build before a director sees it/ wideshot films it.
How it generally works is we get a bunch of stuff and... Something. This something can be as exact as a blueprint (techpack) that clearly marks where furniture is supposed to go or as vague as a one sentence long description of what the set is supposed to be. We are usually given a bunch of options for virtually everything that is used. Then we make up the set.
Then the waveform goes nuts. The Heirachy goes Set Decorator, Production Designer, and then Producer. They will randomly visit or call in sometimes separately and whatever plans that existed immediately cease to matter. The set may completely change a random number of times back and forth as anyone above us in the hierarchy demands unless it countermands a specific demand made by someone above the demander in the hierarchy.
That is until shoot day. Once the Director has the floor all of that prep goes immediately out the window and the director may change whatever they please about the set and while there's usually too much time constraints to change everything it could mean getting rid of anything. The waveform only collapses to depict a singular reality once the wideshot is in the bag which means there is now a continuity that must (okay "must" is a strong word) be obeyed.