Because of my location and age, I tend to be booked primarily but not exclusively by white, British, over 40s - and this applies even when booked by punters in other areas or who travel (quite a few of those who book me are travelling for one reason or another, and or travelling to me/asking me to travel).
That said there is not a pattern of bad experiences linked to any one single demographic. Those who I have had to speak to the police about have been white, male, over 30.
Some people say older 'mature' men make better clients. In my experience some are, some are not and the majority of difficult, dangerous punters/clients I encounter (and I do and they are not uncommon) are (but not exclusively) white, British, over 30. Interestingly despite common belief, I find those in their 20s to be less problematic, could be a numbers thing, but as I get older I seem to be attracting those attracted to MILFs, perhaps that selects out those who have honed in on me.
I am certain someone younger, in a different geographic and urban location, may have different experiences. I can only reflect on my own.