Latest beta build 20068.10 (but it’s been happening for a while, so it’s not a new problem with the beta).
On my iPhone XS, when I turn the device into landscape mode so the notch is on the left, an empty area appears to the right of the settings icon (sorry for my terrible highlighting, the screenshot annotator kept wanting to crop if I started the highlight too far to the side!). This area accepts swipes, but does not accept taps, which makes it difficult to consistently trigger right-side taps.
I’m guessing this is somehow related to the notch handling – when I turn the device the other way so the notch is on the right, the settings icon is up against the edge of the notch as expected.