Steps to reproduce:
1. Create a new Project
2. Create a new Script in the Project Window
3. Create Cube GameObject in the Hierarchy
4. Drag the created script on to the Cube GameObject

Expected result: The Script Component is added once
Actual result: The Script Component is added twice

Reproducible with: 2020.3.45f1, 2022.2.6f1, 2023.1.0b2, 2023.1.0b3, 2023.2.0a1
Not Reproducible with: 2022.2.5f1, 2023.1.0a1, 2023.1.0b1

Reproduced on macOS Ventura 13.1(M1 Max), Mac Intel, Windows 10, Windows 11

Workarounds: Remove one of the scripts added, Add scripts with "Add component" button, Drag and drop script onto the game object in the hierarchy instead of the inspector