Correct me if I'm wrong, but that looks like a telco POTS run to what the phone company people would call a "main frame" (not to be confused with a computer mainframe). This is where your plain old telephone service line from your house enters the phone co. central office. It feeds what amounts to a giant punch-down block, size of a whole room. It's vay old school, before they went to digital cross connects.

If I'm correct (I've only seen these a few times back in the day), then consider this: How often did your old copper phone line go down? Rarely. They had a lot of automatic testing and repair in the old days, plus an army of craftpeople (what they called technicians) who worked like monks to keep this stuff online.

Now let me tell you about the time I saw an old 1AESS electromechanical switch ROOM (yes, it took up the whole floor of a buidling). Damn, I'm old...