Personally, I would reserve the “doctor” title for, in addition to medicine and dentistry, to at least semi hard sciences like the guys who figure out rocket launches.
It could be worse: the Germans refer to lawyers as Doctor...
A snooty maitre d' is on the phone talking to someone. "OK, that's a reservation for four in the name of Dr. Jennings. May I ask if you are a real doctor or just a Ph.D.?"
In Germany, an M.D. is an undergraduate degree
Guess what the "D" stands for in JD...
Many people think the term doctor refers to those who practice medicine. That is not the case.
Before you decide which degree you would recognize, you need to read about the history of the degrees and why others recognize the PhD as the doctoral degree - no matter the discipline in which it was attained.
The term doctor comes from the Latin docere meaning to teach. The Ph.D. is an academic degree, it is not a 'practice' degree. It has been the highest degree since before the 17th century. The MD degree is a much more recent professional degree. The degree is for someone who practices medicine. To be a professor at a medical school you need a PhD.