This makes me feel so much better because we have all sorts of evidence such as house lease, joint bank account,partner declared on tax returns, electricity, gas, internet, phone bills, joint car, health and house contents insurance, mail sent to our joint address, trip overseas etc, but we don't have that many pictures because my partner is not big on pictures. We do have some pictures with family and friends as well as from our trip overseas, about 30 I would say. I have taken screenshots of my pictures showing the date and year when the pictures were taken so that can prove that pictures were taken throughout different periods of time.Easy to fake or edit. Much harder to fake years worth of bank statements, owning a house together, paying vehicle/house/medical insurances, etc.
The way I see it, photos alone don't do much of anything. I don't even think they put photos as an example of things to upload to prove your relationship is genuine and continuing. Therefore, I see them as supplementary.
We just selected ones to correspond with our actual evidence. So if we went on holiday with friends or family, we'd have a PDF of flights, hotels, etc and a photo of us with those friends or family together or in front of a famous landmark or tourist spot. The documents prove we were there. Photo is just extra. We didn't see the need to upload a photo of everything we did on holiday.
Edit: Also why I feel the type of photo matters. A bunch of selfies? We didn't see the point. We could have taken all of them at once for all they know. But a handful of photos showing us with our kids over time? Kids grow fast and you can see that. Physical changes in appearance shows time... someone gaining or losing weight during the relationship, growing a beard, losing the beard, change hair color or style, etc.
Quality over quantity, basically.