> Have you ever noticed just how much of the drama in movies is generated by an unspoken rule that the characters aren’t allowed to communicate well? Instead of naming the problem, they’re forced to skirt around it until the plot makes it impossible to ignore.

That's the core of most of real world issues be it at work or relationships of any type. I can also personally attest most of issues of any type in my megacorp are caused by bad communication. How many times you see a barely functional marriage where unspoken things hang around and one party is afraid to tell them to the other side, and subtle hints are ignored. How many folks from older generations had a good talk about their true sexual preferences for example. Some nationalities have issues speaking frankly, ie British circle around issues with too much politeness. Good luck getting any Indian (in India) telling you "no" or "I don't know" (spent so much time wandering in wrong directions in good ol' times before smart phones).

Remove this issue and psychologists lose 95% of their work. Perfectly clear communication is an exception in this world.

I'd say movies gradually found this topic since many people will find themselves in those movies and identify with struggles of protagonists. Then logically frequent ending resolving many if not all issues allows people to have a little dream of resolving stuff they struggle with (subconsciously or consciously) in their lives.