Oh it's 'blatantly' true that the headrest are for safety. The problem is engineers can't design a perfect one size fits all. So things are designed around averages. It's the best they can do.
If you fall outside of those averages at either end well, there is going to be more risk. As a male who is above average height, automotive headrests add more risk for me just as they do for a smaller woman.
You mean Judaeo-Christian Islamic values. Let's at least be inclusive here.