@LukeAlmighty I think the rocks are nice because it's more natural to the environment than man-made structures made with metal.
It's kind of close to the aesthetic of what a zen garden is you know. With its natural calmness.
It's a lot more boring than what you could do with like artistic freedom and sculpting but you can't deny that it stops people from creating really ugly creations that are going to be permanently there for decades or just blatant inserts of propaganda.
And it is probably way more cheaper for the city or local council to create and add these all around than it is to add unique statues or hire people to create modern art.
Although in this situation I think what is really needed in that Park is more grass or trees because it has a kind of postmodern soullessness to it even with the natural rocks.
And honestly if you just had Moss or flowers growing on the rocks it would probably do a lot to make it look way better