I do not know the numbers or the areas of speciality of the PhDs surveyed by Carnegie Mellon.
However, many PhDs are scientists in some field, or at the very least have a general understanding of the scientific method and how to interpret data and make decisions based on it.
Are you assuming that the 24% of vaccine hesitant PhDs are exclusively or mostly in biology-related fields?
It's possible, but given all the doctors and public health officials who strongly advocate the vaccines, I tend to doubt they would if any significant number of PhD-educated scientist did not.
Regardless, it gets back to what I was referring to when it comes to confirmation biases and how they affect how people interpret things like the Carnegie Mellon study.
As I said, I'll yield to the opinion of the vast majority of those in the medical field on the issue.
If that's the hill I end up dying or growing a lizard tail on, so be it.