I remember this effect (albeit a slightly different aspect of it) being demonstrated on an English children's television show over 40 years ago.

An empty wire cage, "how thick does that wire look", <click> now contains a pacing lion "and now?", <click> now contains a pile of gold "and now".

The wire looked significantly thicker when protecting the gold from you than when protecting you from the lion. Even on a small black and white TV. Even when it was quite obviously the exact same cage.

I wonder what made the authors think this was a newly discovered phenomenon?