This is my understanding also. Insurance Cos are aware of this.

I think people assume that they are receiving worse service from a PA vs a MD.

A PA may have more time to research your condition. They have more experience with your particular condition.

I went to a PA recently when my usual MD was not available. They knew of a recently(ish) released test that could be helpful in the situation. I did the test, and the MD reviewed it. The MD wasn't familiar with the test, but it ended up being very important.