Couldn’t you make the same argument regarding whether testing physics or organic chemistry aptitude is necessary for every specialty? The admissions office could at least nudge students to not pursue surgery if they have poor dexterity.
Well, that sort of already happens, but some schools are admittedly better at this form of "career counseling" than others, and usually well after they have matriculated. At my own school we were required to have such an interview before we started clerkships and faculty members would try to develop this sort of self-insight about where one's skills and aptitudes are best, but years later the students who rotate with me now tell me this is optional, which seems like a step backwards.