>>3415320this
But for the benefit of people who haven't had to deal with this in the variety of possible ways .....yet:
"Fuck off cunt" is usually very efficient. People who assume photo=bad like that make a choice to become offended, so escalating directly to their own endgame often works a charm.
I usually politely/dismissively refuse point blank and disengage with them.
Setting a precedent where you allow people to tell you what to do with your own intellectual and physical property is really stupid. Illegal from their perspective too.
That said; based on their approach I generally go for "sure, whatever", or "lol, why would I do that?", turn away and don't actually delete anything... because I need a photo to recognise them in the future.
Most of the time I also let them know that I took the photo in the first place because they looked cool. Which means that unless i have a photo to see again when culling/postprocessing later that day, I won't remember them and their preference to not be photographed. So next time i see them I'll reflexively photograph them again.
If they express a desire not to be photographed the images effectively cease to exist anyway. Nobody except me will usually ever see them again. But in order to never photograph them again I need a record of what they look like. Seeing their face again when culling is usually enough to set that mental filter.. move the photos to a 'hater' folder, and probably never look at them again...... And if required: so i can identify them to police.
Telling them this if they start to get threatening is a bit of a coin toss though. Usually it makes them back off, but if not then the first thing they will do is assess if they can steal/destroy the camera, and their chances of successfully assaulting you. Looking at them like you know this is what they are thinking is very useful. So is a bodycam.
So yeah, it can be difficult to resist the demand to delete photos. But you almost always should refuse.