I am a photographer. It is my job to go into schools and take candid photos for the yearbook.
The number of kids that are on a 'do not photograph' list isn't large, but it is a non-zero number. If that kid is even out of focus in the background, we do not use that photo.
If a child shows even the tiniest bit upset that there's a person in the room with a camera, I do not take their photo.
At pop culture conventions, I ask people if I can take their photo. Or if I take a candid of them, I track them down and give them my info and get th3ir consent before posting.
At events like parties, concerts, performances, consent is generally implied because these are photographed events, but if an attendee approaches me and tells me to crop them out then I crop them out.
This makes street photography tedious, but I learned in my very first job as a camp counselor that people have very good reasons for not wanting their photo publicized. There are kids in the foster system with abusive parents. There are adults with stalkers. There are people who might be a witness to a crime.
Even outside of this- I've seen how private persons become memes against their will just by going out in public. Some people are super not normal about meme fame.
Leave people alone. The world is complicated. Make your own content.