They did make up SOME stuff. A hole in a Farday cage lets in EM radiation, but the size of the hole determines the frequency. A pinhole in a weld will let in only, say, 90 GHz and up while being completely opaque to lower freqs.
A quarter inch hole lets in (iirc) 2.4 GHz MHz and up. To stop older cell phones, a 1/3 inch mesh will stop 1.8 GHz, and 900 MHz is stopped by a little bigger than 1/2 inch. Basically wavelength/20. Quarter inch hardware cloth will stop most cell phones.
Copper window screening works for AM and FM radio and most TV transmitters and cell phones, I worked in a 2x4 cage covered with screen and for “low” freqs it worked just fine. 20 GHZ not so much.
So a chain link fence will protect you maybe from 1000 Hz or so, so the shielded room in the pic is a fantasy.
OTOH, consider the radiotelescope dish at Ariciebo. It’s made of screening, yet is a very good reflector at the freqs the astronomers use. Hmm, wonder if a cell phone works under there?
An interesting fact related to all this that is unknown to the non EE types is how an RF choke works. A simple coil of wire can totally stop RF energy and yet allow DC to flow freely.
For instance: If you connect an RF choke across a transmitters antenna feed line it will not hinder the flow of RF in the line. It will however create a low resistance path for dc energy to flow between the feedline conductors. If your transmitter is grounded then the choke across the transmission line means your entire antenna system is directly connected to the ground because the braid of the transmission line is connected to ground. This lets static bleed away to the earth and still the antenna functions normally.
The lower the RF frequency the larger the choke needs to be to block it. The one in the image below is the sort typically used in Ham radio work.