Guess what the "D" stands for in JD...
True but it would be a pompous lawyer indeed who, with no other qualifications, would refer to himself as “doctor”.
Further, the switch from the LL.B. to the J.D. is a bit of a modern contrivance. At one point, US law schools universally awarded the LL.B. (a bachelor of laws). Harvard and Yale switched to the J.D. in the 60s / 70s.