[TimPC]

In general, I feel that it's important to make your home environment a safe and comfortable environment. If you feel that exposure therapy is needed to help them adjust to the world (probably true, but I'd want to do this on the advice of a psychologist if possible rather than on my own) do that outside your home where you should be making every effort for them to feel safe and comfortable. So absolutely minimize clutter, reduce screen time and look for other options to make your home feel as safe as possible for your child.