Over my time I have seen more than a few "Great Grandpa"s who could take a whipping more than any of these young pups could even imagine.

I think one's kink is likely to evolve with age and perhaps one loses interest as one's sexuality changes. I have no problem seeing older gentlemen as long as they are of sound mind. My bondage furniture is surprisingly comfortable.

I did have a client I saw a few times, many years ago, who had a massive stroke--not with me, but something that left him unable to make reasonable life choices. I felt that was highly inappropriate for me to see him again. He asked many times, but it just did not seem consensual to me.