Unlock your iPhone with Apple Watch when you're wearing a face mask

You could disable face id before going to sleep.

https://www.imore.com/how-quickly-disable-face-id

In the morning you will need to use your Pin to unlock your iPhone, but from then on, you can use your Apple Watch.

You can disable the Apple Watch/iPhone unlock from your Apple Watch settings, and enable it again in the morning.

You can put your watch on your wrist, but not unlock it, so it cannot unlock your iPhone.

The primary reason for this feature is so when you need to use your iPhone when out in public wearing a mask. All you have to do while sleeping is break one of the items in the secure chain to keep the Apple Watch from unlocking your iPhone while you are asleep.

If you cannot control your environment sufficiently to maintain security, then do not use the Apple Watch to unlock your iPhone. It is not required, and it is off by default because there is limitation.

If you have better suggestions for Apple, then use the feedback link

https://www.apple.com/feedback/watch.html

This is a user helping other users with tech questions

forum, you are not addressing apple here  just  fellow users

you can inform apple about the issue using their feedback

Feedback - Apple Watch - Apple