No, it's not needed. My theory is that they picked that shape intentionally to match the notch on the iPhones. They could have gone with a much tinier notch, since that notch is only hiding a single web-cam lens. The notch on the iPhones also holds the FaceID cameras and tech, but for some reason Apple refuses to put FaceID on their laptops where it would be much more useful. I suspect they'll make it much smaller in the future or change it to a "dynamic island" notch instead.
I don't think FaceID is a good idea on the computer. On the phone it unlocks when the device is quite close to you, but I suspect someone could sit down at your computer and watch it unlock if you are behind them. Touching the keyboard or just using your watch is more secure.
Of course if you were in the kind of environment where it might be a problem if your computer unlocked as you walked by, you probably wouldn't enable the feature anyway. As it is I am annoyed by iphone and ipad apps that require faceid or other login each time as I'm the only one who uses those devices anyway.
Nevertheless I think faceid on the laptop or imac is an insecure idea.
