re: People with the title of “Dr.” who aren’t doctors

I have a clinical doctorate as a physical therapist. Went to graduate school for three years, performed research appropriate in my field and had it published. I hold the highest clinical degree in my field and am an expert in my field. I practice with autonomy and you don’t need a physician referral to see me or for me to bill for my services. I don’t ask people to call me doctor but many do out of respect for my degree. Many don’t and that’s okay too. How is that any different than a PhD with the exception of a dissertation defense? What has the PhD done that earns that title more than me?