With the current version of Photoshop, the Tree filter allows you set the Camera Tilt in advanced options, but the range of settings only work from eye level to looking from below. Is there any reason why the camera tilt doesn't allow for a render from a bird's eye view or above normal eye level?
Being able to render trees from top-down would be incredibly useful for cartography, exterior design, and a host of other cases.
The render trees filter is drawing in 2D and whilst camera tilt changes the shape it is not the same as a 3D model where you can fly the camera above and around it. You could use 3D models or put a feature request ("idea") into the link below, where it is more likely to be seen by Adobe staff.