I think it's the lighting/color grading from the sun being near its zenith, combined with the point of view. Makes it look like something that was rendered with ambient occlusion and contact shadows turned off.

Edit : also it just looks like a typical isometric game's viewing angle

Looks like an isometric game, like Project Zomboid.

edit: isometric not isotropic lol

Probably due to the scale provided by people and emergency vehicles.