He's a "fine art photographer" and I think we all know what that means. As far as street photography goes, it's always best to flash a smile or just explain to the people you're a street photographer documenting city life. If they ask for it to be deleted "sorry, film cannot be unexposed." I understand his gist, which is to not be a jerk with a camera, but the solution isn't to stop taking photos on the street.
That being said I do think there are way too many cameras out there these days in one form or another. I also think people are much less open photo-wise than say 10 years ago.
But one would think people should be used to getting shot with all the cell phones and little cams waving around in the world.