@BestBoy
So, before I get into this, I want to point out that the reason therapists/doctors can't have personal relationships with their patients is NOT due to some "inherent power dynamics," it's because it has the possibility of literally negatively affecting their mental and/or physical health, if things go south in said personal relationship.
As for the rest of those, are you aware that those rules and ethics violations also apply to just normal, friendly relationships as well? That is also considered an ethics violation. And it's not because ALL leader/subordinate relationships are "inherently" ethics violations, it's to protect the employer's reputation, because the possibility would then exist for the person in the leadership position to have the ability to compromise their integrity. Just because the possibility exists, does not mean it will happen. If I'm playing the lottery, there's a possibility that I'll win the jackpot, because I bought a ticket. That does not mean, in any way, that I WILL win the jackpot, just by virtue of buying a ticket.
Are you also aware that, in the military, it is a violation of the UCMJ for an officer to be in an "unduly familiar personal relationship" with an enlisted member (their subordinate)? This ranges from just being too casual with the enlisted member, all the way to an intimate relationship with them. If so, are you also aware that the Army is the only branch that does not penalize their enlisted/officers for that fraternization? Or that across all branches, if you knew the enlisted/officer before you were enlisted/commissioned, you are exempt from fraternization charges? Now, if that type of relationship is "inherently" an ethics violation, then why is it not reprimanded uniformly, across the board? The only truthful answer to that question would be because there is nothing "inherently" unethical about that situation. The only violations occur when someone decides to take advantage of a situation that they have the ability to exploit, as is the case with literally every other facet of humanity.
Also, if you think that only applies to the military, then I would also like to point out that you neglected to mention that not ALL schools and learning facilities have the same rules on teacher/student relationships as Cornell, Gordon, Michigan, and Oregon. Many more universities are completely fine with those relationships, so long as the student is over 18 years of age and it cannot be proven that the teacher is giving preferential treatment to that student, by threat of termination. The biggest case against student/teacher relationships are that the student is usually underage, which is of course, very illegal.