LOL.... there is a big difference between the AMA and the USTA. The medical professional is heavily regulated at both the state and federal level. That's why you have law like HIPAA in place. Those things do not exist with USPTA.
If you need a heart surgery or transplant, you just can not go down the street and have it done. When mistakes happen, people die. That's why you have malpractice insurance.
If you get bad tennis lessons from at certified USPTA, nobody die and it is considered "fee for service". Are you going to sue the instructor?
My point was that despite tennis not being a critical profession, once the new system kicks in, it will continue and the free market will not compel clubs to hire others.