You are giving the average American population entirely too much credit. At least 70% of them wouldn't know what "empirical evidence" was if it slapped them in the face.
I don't really care what they are basing their decision on. It is their life to live. I'll make my own personal decision and assuming the vaccines are as effective as advertised, then I'll be safe from anyone that chooses not to be vaccinated.
If I had a job where I was in contact with people, or had a family at home to protect, or if my health put me at greater risk of serious covid complications, then I would already be in line to be vaccinated. Fortunately none of those are the case and I can safely keep a "wait and see" approach without assuming unreasonable risk.