`bool | None` considered dangerous

i think there is another issue similar to this, but just thought i'd reiterate it here

The issue only identifies `bool | None` and does not name a source file, test, or expected diagnostic. Start by reproducing how basedmypy handles that annotation and inspect related issues for the intended behavior. Done means the expected treatment is agreed and covered by a regression test.

Written by the indexing model from the issue text.