These requests appear to be violations of University policies regarding the review and approval of dissertations.
Your dissertation is approved by your committee according to written policies of your university or graduate school, not only by your advisor. It is not unusual for the committee to either request changes or suggest changes or to approve a dissertation subject to certain changes.
Changes should all be minor, mostly stylistic. Substantive changes should have been worked out before the stage of committee approval.
I suggest you get all the history of the requested changes together and organized to meet with others.
First meet with your advisor/chair and get clarity on agreement or disagreement on with each and every item. Keep in mind that it is your dissertation but it must meet the standards of the university and the profession when having these discussions. Suggestions should be taken seriously and deserve a response but that does not require that your dissertation be rewritten.
At the same time, identify the person or persons at your department or university who is the next step of appeal. Know this person's office, eg, Associate Dean, name, and phone number before meeting with your advisor.
If you and your advisor/chair have different views of whether changes should be made, then ask to meet with your advisor and the named officer together to discuss the next step. If you advisor declines then meet with the named officer yourself. Explain what has happened in detail. Ask the named officer how to proceed according to university policy. Be sure to say this. You are not there for personal advice. You want the university and its faculty, particularly your advisor, to adhere to university policy, absolutely and completely.
Any further recommendations depend completely on the procedures approved by your university or by designated agents, eg, the Dean of the Graduate School in many cases.
Please keep in mind that your advisor might not understand how serious it is to comply with university policy. Your advisor does not get to decide whatever they want will- nilly. You want someone in an administrative position of authority to explain to your advisor what they and you can do now that your dissertation has been approved.
It is possible that you might obtain legal counsel in this matter. A dean or other higher officer knows that and will see to it that university policy is adhered to completely, both by your advisor and by you.
You are not the first. Good luck.