At which point it's already too late - the hacker has had access to your camera for some period of time, until you notice the light. If you're interested in stopping people seeing you then you've failed. Putting a hardware block on the camera (eg tape) before you're hacked means that the hacker won't ever get access to your camera to see you.

The hardware block is about stopping people accessing your camera. It has no effect on anything else.

Regardless of what you do with your camera you still have to defend against other ways you can be hacked.