Operating system: Windows 10
Graphics card: GeForce GTX 1070/PCIe/SSE2
Broken: 2.83.2, branch: master, commit date: 2020-07-09 05:50, hash: 239fbf7d936f, type: Release
The vertex normals for this part are not aligned to the correct direction causing incorrect shading.
Exact steps for others to reproduce the error
I am unsure of the exact modelling steps that lead to this issue. However, the entire process was done in the aforementioned version of Blender.
The incorrect vertex normals seem to be linked to the object somehow. Adding a circle into the existing object and remodelling the part reproduces the exact same incorrect normals, but adding a new circle object, enabling smooth shading, auto-smooth normals and the mirror modifier, then modelling the part leads to a properly shaded object with correct normals.