Nah seems like pictures choosen for this purpose? Or do you mean they will sneak in a picture with an unknown date every now and then to good estimators?

Something like this, pretty much.

I doubt why they need to, these photos are all from newspaper which already have the date.

Eh, we already had a discussion a few days ago about people using AI to effortlessly geolocate photos. That's the "where". I could see a model that also provides the "when" as useful for a lot of purposes.