For some reason, possibly speed the dr always insisted that you were nude and ready for him. I'm usually told by my female doctor that I can either take everything off and wear a gown, or wear just my underwear. You had to access the examination room via the matrons nurses office so no one could accidentally come in but it did cause your heart to jump when the door opened. Some men have religious reasons for their modesty, amongst other reasons. I could care less if you want a gown or not.
Even then, it's for the minimum necessary time.
I never sat on the table naked. Vicious Spanking. Let's face it, how many serious illnesses are going to be diagnosed when you have your exam in your boxers vs an examination with a gown on?