Sometimes, you may want to keep your solutions and editorial hidden from alters/reviewers until a certain time.
A toggle button in these tabs can be used for this purpose. For instance, if the button is toggled on, only then users other than setter himself can see the corresponding tab.
One argument can be that this can be handled by not uploading the solutions or editorial, but that makes management a little bit harder.
I will add an option to mark solutions as draft/private. When enabled, only the author of the solution can see it.
The “Tester” share access is actually meant for this purpose where others cannot see the details of a problem’s implementation (e.g. tests, custom checker, etc), but can see the statement and try out different solutions. May be the way to go would be to give testers a place to store their solutions.