This is a topic that has been covered many times, but is still an issue in Rhino 8.
When a new layer is created it shows as visible in all existing details. Using an “old” detail then requires going in and turning off all newly created layers in that detail.
Improvements in Rhino 8 such as Layer Off/On In this Detail help in this regard, but they do not solve the problem.
There is a plugin that addresses this, (SafeLayout) but this too seemed to have bugs and in one case seemed to go haywire and turned on all layers in all details in all layouts in a file with 300 plus layout pages. So I stopped using it.
But the simple request is to set visibility for all new layers to OFF by default. This gives the user full control over layer visibility in details.
I am going to work on a script to address this, but it seems this should best be handled when new layers are created.
Maybe I’m missing something, but I’ve been through every existing post on this topic and can’t see a full resolution.