in the 70s-80s etc, they had those vertical leg presses, and some today
remember on the road with Ronnie coleman? he uses one thats vertical too.
but much safer, and a stack version instead of plate loaded.
I think the pic is very old. Back in the day of Sandow, Grimek, Lelanne "balance" was a very important part of the training. Remember those old pics with bodybuilders doing "gymnastic" feats of balance etc? Maybe that is why this guy is trying that leg press
Back bridges are actually a great, underrated exercise. Most people think it's bad for your lower back and spine, but no one really looks into it. Try searching some info on it and you'll find it to be very helpful, in fact. It helps build strength in your lower back and neck that no weight lifting exercises could do.
Although, I have no idea wtf he's doing with the weight. That could be pretty dangerous...