I had the same thought as VanJan - proximity of the B star to the primary is a common cause of close companions looking less bright than they are. The magnitude for B is double decimal, which means a modern photoelectric magnitude, perhaps Tycho, not an older eye estimate.
I looked through my observing records from the Northern hemisphere, since the Declination of this double double is barely above my Northern horizon from SE Australia. I have notes of STF 2681 from a night of better conditions than your recent night, John. My notes say "no cloud or haze, crescent Moon, seeing fair+.
With a C8 at 80x all four stars were seen, B looking quite near star A. Going to 135x improved the visibility of B and the D wide companion to C, but they didn't require averted vision at 80x. So the observing conditions were reasonable, despite a suburban location. The naked eye limit there was typically around mag 5 with crescent Moon, similar to where I live now. It's a neat little group but less striking than some others, such as Epsilon Lyrae and Nu Scorpii.