By civil law only. A criminal act it is not. That means unless the person takes it into their own hands to sue, nothing will happen. Still, you take on quite a legal risk if you publish footage that shows strangers, because you’ll never know when they will turn up and sue you for damages. It could happen 10 years down the line, and the amount of damages they can claim will be even higher the longer the footage has been published.
It is not criminal to _shoot/film_, however it is a criminal act to _publish_ videos/photos with people when they have not consented. There are many exceptions though (famous persons, people accidentally in the picture not being the focus, public demonstrations and other events — maybe not the best translations, just to give some ideas)
Yet how many millions of Europeans in countries with laws of this sort have appeared on Instagram, Flickr, TikTok, etc.? It may be technically the case but essentially no one worries about it--especially those who aren't going to shove a camera in someone's face.
Entities, i.e. companies, are pretty careful everywhere about publishing photos of people for marketing purposes (which any website is) without permission of some sort. Whether it's in the terms of attending an event or it's a stock photo which presumably has a release form. I doubt individuals in Germany are much less indiscriminate about sharing on Instagram, Twitter, Flickr, and elsewhere than they are most places. And German law has very little teeth if the people doing the sharing aren't German.
