Okay haven’t played with it yet. but there is also page publishing.
I would imagine the code may help to get some ideas. There are a few components that use user fields. A more recent addition is a kind of watched words for the member that will hide? posts with word term.
There are also some theme-components that use a switch toggle in iirc Hamburger menu or header.
Custom header links may work as well possibly.
I am not sure but with a checkbox? you might be able to copy the link for that user prefer checkbox.