In almost all settings sub-menus in newer android versions, there is a item in the list called "Advanced" closest to the bottom, that shows additional settings when pressed. This is apparently a design goal called Progressive disclosure, according to Android Settings Design Guidelines
I am wondering if the "Progressive disclosure" feature can be disabled somehow, so that I am shown all settings in sub-menus by default.
It is how the developer of that Android ROM designs the settings screen. There is no user-end setting to decide how the settings show up and /or to sort them in different ways. As it is a Google instruction to hide less used settings inside the "Advanced" menu, most developers will decide on pushing additional settings behind that menu item. In fact my current phone did that even when there weren't at least 3 items in the advanced menu.
Short answer: It is not possible to show the settings outside of the "Advanced" sub-menu. There's no way for users to disable the use of Progressive Disclosures.
Root and modification can help in adjusting the priority/place of that setting item. But that's probably too much effort to achieve much lesser.
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