How to reproduce:
1. Open the user's attached "ReorderableMissing.zip" project
2. Open "SampleScene" Scene
3. Select "GameObject" GameObject in the Hierarchy window
4. Expand the "Test List" and then "Element3>Subs>Element0>Textures" property in the Inspector
5. Observe the Inspector window
6. Hold Alt key and click on "Types" list
7. Observe the Inspector window

Expected result: Correct indentation for the "Subs" list, "Test" and "Test 2" headers are taken into account, no overlapping on the list names (step 5). Holding the Alt key and clicking on the foldout triangle folds out everything that is present in the list, including the nested list items (step 7).
Actual result: Incorrect indentation for "Subs" list, "Test" and "Test 2" headers are not properly taken into account, "Test 2" header overlaps the reorderable list "Types" (step 5). Holding the Alt key and clicking on the foldout triangle does not fold out the nested list items (step 7).

Reproducible with: 2021.1.1f1, 2021.2.0a8, 2021.2.0a12
Not reproducible with: 2020.3.2f1, 2021.2.0a7
Could not test with: 2018.4.24f1, 2019.4.2f1, 2020.1.0b14 (Reorderable lists were internal)

Notes:
- Adding a GameObject field below the reorderable list blocks the + and - signs to add items into a list
- Having NonReorderable attribute on all of the lists results in no such issues
- Reorderable list names are bold (might be intentional)
- Attached a video with all the of the mentioned issues also showing what happens if a GameObject field is added below the reorderable list
- Reproducible on Windows 10 and Ubuntu 18.04