Here’s a fun fact: “Doctor” was an academic degree. It was originally meant for theology, but expanded as the scope of academia expanded and natural philosophy became the sciences. We still call the degree “Doctor of Philosophy” as a result of that. Being a doctor of something meant that you were qualified to conduct research and teach at the university level. It eventually meant that you have made a contribution to your field - your dissertation - and the expectation was that you had and would continue to publish research papers in scientific journals.
The idea of a “medical doctor” was a new addition. MDs don’t do research, didn’t do a dissertation, and in general are not equipped to teach and advance the academic understanding of their field.
So I agree. Scientists should get the blue shirts, physicians and surgeons should just wear scrubs.
In Germany a doctor in medicine has to write a dissertation subject to a specific topic that deepens scientific understanding. Having a few articles in science magazines is also usual.
In Germany there are also two words, “Doktor” (the academic title) and “Arzt” (a medical professional). If your “Arzt” hasn’t published a dissertation, you technically shouldn’t be calling them “Doctor”, but “Herr“/“Frau” <surname>. Very few people care about this distinction, though.
Where did you get that idea? In Germany the average medical student(!) writes a dissertation that's at most comparable to a masters thesis in other natural sciences... And all of that within a time frame of 6 months. Many don't even bother with that any more.
Of course, there are also medical students that go into research and really deepen scientific understanding. But that's by far the exception.
I have quite a few friends that studied medicine and are now working as "Facharzt" in hospitals. All said they needed to have 4 published articles as author's or co author's plus a dissertation just to start the journey of becoming specialized doctors. Their degree was after they defended their dissertations.
Doctor comes from latin (from the verb docere - to teach) and basically means teacher, or someone with enough knowledge in a field to teach. The term is still used as an academic title, but in different way in different countries. For example, while in english speaking countries ot is used for someone who completed their PhD (phylosophæ doctorate), so someone with enough knowledge to do research and teach to an academic level, in Italy the title "dottore" is given to any who got a degree, even a Bachelor's, so a physician is a doctor in medicine because they graduated in medicine.
There are MDs who do substantive research in medicine and surgery. However, basic science questions and a lot of the applied research are done by MD/PhDs. The dual degrees are a signal that the person holding them is not giving MMR vaccinations to kids or fixing broken arms, but who are committed to doing active research. It’s not an absolute requirement - I’ve worked with brilliant MDs at the VA and UC facilities who are gifted researchers. I’m painting with a very broad brush there.