Thank you for the suggestion.
It seems to be interesting but I’d like to know why you need to temporarily hide notebooks.
I guess it’s mostly enough if you switch to a workspace view.
Regarding the lock feature, please refer to the existing topic:
In my opinion, while muting and locking are useful for some people, they are kind of confusing for some people.
I can imagine that I will get reports like “I can’t edit a note!” and “a notebook is lost!”.
So, we have to consider such features very carefully.