I appreciated BCD because the in-memory data represented in hex (as by an 80's era debugger) was exactly the decimal value. As I recall, debuggers of that time

I appreciated BCD because the in-memory data represented in hex (as by an 80's era debugger) was exactly the decimal value. As I recall, debuggers of that time only understood two datatypes: ASCII characters and hex octets. On consideration, I think my COBOL compiler's ability to define arbitrary-precision fixed-length numerical variables wasn't down to the use of BCD; you can do that with other binary encodings. But I worked for Burroughs at the time; their processors had hardware support for BCD arithmetic, so it was fast. The debugging convenience came with no great cost.