Which is the best method to know all the gameObject seen by a camera?

I’m trying to get all the gameObject seen by a camera and then destroy all of them, but with GeometryUtility.TestPlanesAABB I have to do a list of all the gameObjects, that make the Frame Rate very low. So there are other methods?

A renderer knows when it is visible to a camera. You can create a script which destroys a gameobject when visible using render.visible

if(renderer.isVisible) Destroy(gameObject);

Attach that script to any object you want to be destroyed when visible.

Also OnBecomeVisible is called when an object becomes visible to a camera.